Editing Rhine (section)

==Geography==
[[File:Rhein-Karte2.png|thumb|right|270px|upright=1.2|<u>'''Sections of the Rhine:'''</u> {{legend|#ff7474|[[Rhine–Meuse–Scheldt delta]]}} {{legend|#ff8c35|[[Lower Rhine]]}} {{legend|#ffff27|[[Middle Rhine]]}} {{legend|#82b143|[[Upper Rhine]]}} {{legend|#4abbb7|[[High Rhine]]}} {{legend|#2d7cea|[[Lake Constance]] (''[[Untersee (Lake Constance)|Untersee]]'', ''[[Seerhein]]'', ''[[Obersee (Lake Constance)|Obersee]]'')}} {{legend|#ba7eff|[[Alpine Rhine]], ''[[Vorderrhein]]'', ''[[Hinterrhein (river)|Hinterrhein]]''}} {{legend|#ffffff|[[Sources of the Rhine|Rhine sources]]}} For an interactive map, click here: {{maplink|from=Rhine.map}}.]]
The length of the Rhine is conventionally measured in "Rhine-kilometers" (''Rheinkilometer''), a scale introduced in 1939 that runs from the 0&nbsp;km datum at [[Old Rhine Bridge (Constance)|Old Rhine Bridge]] in the city of [[Konstanz]], at the western end of [[Lake Constance]], to the [[Hook of Holland]] at 1,036.20&nbsp;km.

The river is significantly shortened from its natural course due to a number of canal projects completed in the 19th and 20th centuries.{{notetag|most notably the straightening of the Upper Rhine planned by [[Johann Gottfried Tulla]], completed during 1817–1876.}} The "total length of the Rhine", to the inclusion of Lake Constance and the [[Alpine Rhine]] is more difficult to measure objectively; it was cited as {{convert|1232|km|mi|abbr=off|sp=us}} by the Dutch Rijkswaterstaat in 2010.{{notetag|name=length}}

Its course is conventionally divided as follows:
{|class="wikitable"
|-
!Length || Section || Avg. discharge || Elevation || Left tributaries{{efn-lr|name="partial"|Partial list.}} || Right tributaries{{efn-lr|name="partial"}}
|- 
| 76&nbsp;km{{efn-lr|Length of the [[Anterior Rhine]], including the [[Rein da Medel]]; {{cvt|76|km|disp=out}}.}} || The various [[sources of the Rhine|sources]] and headwaters forming the '''[[Anterior Rhine|Anterior]]''' and '''[[Posterior Rhine]]''' within [[Grisons]], Switzerland || 116&nbsp;m<sup>3</sup>/s{{efn-lr|Average runoff for the Rhine catchment for the years 1961–1990 as measured at [[Chur]].{{sfn|Schädler|Weingartner|2002|loc=Table 1, row 10-4}}}} || 584&nbsp;m || [[Aua Russein]], [[Schmuèr]]<ref name=STVR>{{cite map |publisher=Federal Office for the Environment FOEN |url=https://s.geo.admin.ch/69348abdd3 |title=Vorderrhein |map-url=http://www.gewiss.ch |map=Maps of Switzerland – Swiss Confederation – GEWISS |type=online map |language=de |date=2014 |place=Berne, Switzerland |cartography=Swiss Federal Office of Topography swisstopo |via=map.geo.admin.ch |scale=Gewässernetz 1:2 Mio |series=National Map 1:200 000 |access-date=4 January 2016}}</ref> || [[Rein da Tuma]], [[Rein da Curnera]], [[Rein da Medel]], [[Rein da Sumvitg]] ([[Rein da Vigliuts]]), [[Glogn]] ([[Valser Rhine]]), [[Rabiusa]], [[Hinterrhein (river)|Rein Posteriur/Hinterrhein]] (tributaries of which include the [[Ragn da Ferrera]], [[Albula (river)|Albula/Alvra]], [[Gelgia (river)|Gelgia]], and [[Landwasser]])<ref name=STVR/>
|-
| {{abbr|c.|Circa}}&nbsp;90&nbsp;km{{efn-lr|{{cvt|90|km|disp=out}}.}} || The '''[[Alpine Rhine]]''' running through the Grisonian and St. Gall Rhine Valley (partly forming the Swiss border with [[Liechtenstein]] and [[Austrian-Swiss border|Austria]]) || 245&nbsp;m<sup>3</sup>/s{{efn-lr|Average runoff for the Rhine catchment for the years 1961–1990 as measured at the Swiss border immediately upstream of Lake Constance.{{sfn|Schädler|Weingartner|2002|loc=Table 1, row 10-6}}}} || 400&nbsp;m || [[Tamina (river)|Tamina]], [[Saar (Rhine)|Saar]]<ref name=STAR>{{cite map |publisher=Federal Office for the Environment FOEN |url=https://s.geo.admin.ch/6934a65dad |title=Alpenrhein |map-url=http://www.gewiss.ch |map=Maps of Switzerland – Swiss Confederation – GEWISS |type=online map |language=de |date=2014 |place=Berne, Switzerland |cartography=Swiss Federal Office of Topography swisstopo |via=map.geo.admin.ch |scale=Gewässernetz 1:2 Mio |series=National Map 1:2 Mio |access-date=4 January 2016}}</ref> || [[Plessur (river)|Plessur]], [[Landquart (river)|Landquart]],<ref name=STAR/> [[Liechtenstein inland canal]], [[Ill (Austria)|Ill]], [[Frutz]]
|-
| c.&nbsp;60&nbsp;km{{efn-lr|{{cvt|60|km|disp=out}}.}} || '''[[Lake Constance]]''', including the short channel called [[Seerhein]] at [[Konstanz]], connecting [[Obersee (Lake Constance)|Obersee]] and [[Untersee (Lake Constance)|Untersee]] || 364&nbsp;m<sup>3</sup>/s{{efn-lr|Average runoff for the Rhine and Lake Constance catchment for the years 1961–1990 as measured at [[Rheinklingen]].{{sfn|Schädler|Weingartner|2002|loc=Table 1, row 10-7}}}} || 395&nbsp;m || [[Alter Rhein]] (''Rheintaler Binnenkanal''), [[Goldach (river)|Goldach]], [[Aach (Arbon)|Aach]]<ref name=STLC>{{cite map |publisher=Federal Office for the Environment FOEN |url=https://s.geo.admin.ch/693cf9db17 |title=Lake Constance |map-url=http://www.gewiss.ch |map=Maps of Switzerland – Swiss Confederation – GEWISS |type=online map |language=de |date=2014 |place=Berne, Switzerland |cartography=Swiss Federal Office of Topography swisstopo |via=map.geo.admin.ch |scale=Gewässernetz 1:200 000, Flussordnung |series=National Map 1:2 Mio |access-date=5 January 2016}}</ref> || [[Dornbirner Ach]], [[Bregenzer Ach]], [[Leiblach]], [[Argen]], [[Schussen]], [[Rotach]], [[Brunnisach]], [[Lipbach]], [[Seefelder Aach]], [[Stockacher Aach]], [[Radolfzeller Aach]]{{efn-lr|Most of the water of the Radolfzeller Aach comes from the [[Danube Sinkhole]], making the [[Danube]] indirectly a tributary of the Rhine.}}<ref name=STLC/>
|-
| c.&nbsp;150&nbsp;km{{efn-lr|Konstanz to Basel, ''Rheinkilometer'' 0–167; {{cvt|150|km|disp=out}}.}} || The '''[[High Rhine]]''' from the exit of Lake Constance to [[Basel]], forming a substantial part of the [[German-Swiss border]] || 1,089&nbsp;m<sup>3</sup>/s{{efn-lr|Average discharge for the years 1961–1990 as measured at Basel.{{sfn|Schädler|Weingartner|2002|loc=Table 1, row 10-12 "Rhein–Landesgrenze (Gesamtgebiet)"}} Discharges of 2,500&nbsp;m<sup>3</sup>/s are regularly achieved during annual peaks, and discharges of over 4,000&nbsp;m<sup>3</sup>/s have been recorded during exceptional flooding events.<ref>{{cite journal |last1=Scherrer |first1=S. |last2=Petrascheck |first2=A. |last3=Hode |first3=H. |title=Extreme Hochwasser des Rheins bei Basel – Herleitung von Szenarien |journal=Wasser Energie Luft |date=2006 |volume=98 |issue=1 |page=43 |url=http://www.scherrer-hydrol.ch/pdf/scherrer/scherrer_etal_wel_2006_extreme_hochwasser_HQ.pdf |trans-title=Extreme Flooding of the Rhine near Basel - Derivation of Scenarios |publisher=Schweizerischer Wasserwirtschaftsverband |location=Baden |language=de |issn=0377-905X}}</ref>}} 
| 246&nbsp;m|| [[Thur (Switzerland)|Thur]], [[Töss (river)|Töss]], [[Glatt (river)|Glatt]], [[Aare (river)|Aare]],{{efn-lr|At the confluence of the Aare and the Rhine, the Aare at 564&nbsp;m<sup>3</sup>/s{{sfn|Schädler|Weingartner|2002|loc=Table 1, row 20-10}} carries more water on average than the Rhine at 442&nbsp;m<sup>3</sup>/s,{{sfn|Schädler|Weingartner|2002|loc=Table 1, row 10-10}} so that hydrographically speaking the Rhine is a right tributary of the Aare.}} [[Sissle]]. [[Möhlinbach]], [[Ergolz]], [[Birs]]<ref name=STHR>{{cite map |publisher=Federal Office for the Environment FOEN |url=https://s.geo.admin.ch/693cf9db17 |title=High Rhine |map-url=http://www.gewiss.ch |map=Maps of Switzerland – Swiss Confederation – GEWISS |type=online map |language=de |date=2014 |place=Berne, Switzerland |cartography=Swiss Federal Office of Topography swisstopo |via=map.geo.admin.ch |scale=Gewässernetz 1:2 Mio |series=National Map 1:2 Mio |access-date=5 January 2016}}</ref> || [[Biber (Rhine)|Biber]], [[Durach (Rhine)|Durach]], [[Wutach (river)|Wutach]], [[Alb (Southern Black Forest)|Alb]], [[Murg (Southern Black Forest)|Murg]], [[Wehra]]<ref name=STHR/>
|-
| 362&nbsp;km{{efn-lr|Basel to Bingen, ''Rheinkilometer'' 167–529; {{cvt|362|km|disp=out}}.}} || The '''[[Upper Rhine]]''' from Basel to [[Bingen am Rhein|Bingen]] forming the [[Upper Rhine Plain]] and in its upper course the [[Franco-German border]] || || 79&nbsp;m || [[Birsig]], [[Ill (France)|Ill]], [[Moder (river)|Moder]], [[Lauter (Rhine)|Lauter]], [[Nahe (Rhine)|Nahe]] || [[Wiese (river)|Wiese]], [[Kander (Germany)|Kander]], [[Elz (Rhine)|Elz]], [[Kinzig (Rhine)|Kinzig]], [[Rench]], [[Acher]], [[Murg (Northern Black Forest)|Murg]], [[Alb (Northern Black Forest)|Alb]], [[Pfinz]], [[Neckar]], [[Main (river)|Main]]
|-
| 159&nbsp;km{{efn-lr|Bingen to Cologne, ''Rheinkilometer'' 529–688; {{cvt|159|km|disp=out}}.}} || The '''[[Middle Rhine]]''' between Bingen and either [[Bonn]] or [[Cologne]] is entirely within Germany, passing the [[Rhine Gorge]]; || || 45&nbsp;m || [[Moselle (river)|Moselle]], [[Nette (Rhine)|Nette]], [[Ahr]] || [[Lahn]], [[Wied (river)|Wied]], [[Sieg (river)|Sieg]]
|-
| 177&nbsp;km{{efn-lr|Cologne to the Dutch-German border, ''Rheinkilometer'' 688–865.5; {{cvt|177|km|disp=out}}.}} || The '''[[Lower Rhine]]''' or {{lang|de|Niederrhein}} downstream of Bonn, passing the [[Lower Rhine region]] of [[North Rhine-Westphalia]]|| || 11&nbsp;m || [[Erft]] || [[Wupper]], [[Düssel]], [[Ruhr (river)|Ruhr]], [[Emscher]], [[Lippe (river)|Lippe]]
|-
| c.&nbsp;50&nbsp;km{{efn-lr|{{cvt|50|km|disp=out}}.}} || The '''[[Nederrijn|Nether Rhine]]''' or {{lang|nl|Nederrijn}} (shortened course of [[Oude Rijn (Gelderland)|Oude Rijn]] within the [[Rhine–Meuse–Scheldt delta]] in the Netherlands) || 2,900&nbsp;m<sup>3</sup>/s{{efn-lr|The total discharge of the Rhine is subject to significant fluctuations, and average values cited vary between sources; the total discharge given here consists of:
[[Maasmond]], 1450&nbsp;m<sup>3</sup>/s;
[[Haringvliet]], 820&nbsp;m<sup>3</sup>/s;
[[Den Oever]], 310&nbsp;m<sup>3</sup>/s;
[[Kornwerderzand]], 220&nbsp;m<sup>3</sup>/s;
[[IJmuiden]], 9&nbsp;m<sup>3</sup>/s; and the
[[Scheldt–Rhine Canal]], 10&nbsp;m<sup>3</sup>/s.}} || 0&nbsp;m || [[Meuse (river)|Meuse]] || [[Oude IJssel]], [[Berkel]]
|}

{{notelist-lr}}

===Headwaters and sources===
====Sources====
{{Main|Sources of the Rhine}}
[[File:Above Tomasee.JPG|thumb|[[Lake Toma]] seen from the Rhine's upstream end]]
The Rhine carries its name without distinctive accessories only from the [[confluence]] of the [[Vorderrhein|Rein Anteriur/Vorderrhein]] and [[Hinterrhein (river)|Rein Posteriur/Hinterrhein]] next to [[Reichenau, Switzerland|Reichenau]] in [[Tamins]]. Above this point is the extensive [[drainage basin|catchment area]] of the [[headwater]]s of the Rhine. This area belongs almost exclusively to the [[cantons of Switzerland|Swiss canton]] of [[Grisons]] ({{lang|de|Graubünden}}), ranging from [[Saint-Gotthard Massif]] in the west via one valley lying in the [[canton of Ticino]] and [[Province of Sondrio|Sondrio]] ([[Lombardy]], Italy) in the south to the [[Flüela Pass]] in the east. The Rhine is one of four major rivers taking their source in the Gotthard region, along with the [[Ticino (river)|Ticino]] (drainage basin of the [[Po (river)|Po]]), [[Rhône]] and [[Reuss (river)|Reuss]] (Rhine basin). The [[Witenwasserenstock]] is the [[triple divide|triple watershed]] between the Rhine, Rhône and Po.

Traditionally, [[Lake Toma]] near the [[Oberalp Pass]] in the Gotthard region is seen as the source of the Anterior Rhine and the Rhine as a whole. The Posterior Rhine rises in the [[Rheinwald]] below the [[Rheinwaldhorn]].

====Anterior Rhine and Posterior Rhine====
{{main|Vorderrhein|Hinterrhein (river)}}
[[File:Rheinzusammenfluss.JPG|thumb|The confluence of the Anterior Rhine to the lower left and the Posterior Rhine in the background forms the [[Alpine Rhine]] (to the left) next to [[Reichenau, Switzerland|Reichenau]].]]
The source of the river is generally considered north of ''[[Tomasee|Lai da Tuma/Tomasee]]'' on ''Rein Anteriur/Vorderrhein'',<ref>{{Cite web |url=http://www.atlasderschweiz.ch/atlas/en/trial_version/ |archive-url=https://web.archive.org/web/20110609183630/http://www.atlasderschweiz.ch/atlas/en/trial_version/ |title=Atlas der Schweiz Switzerland maps by Swiss Federal Office of Topography |archive-date=9 June 2011}}</ref> although its southern tributary ''[[Rein da Medel]]'' is actually longer before its confluence with the Anterior Rhine near [[Disentis]].

:The '''Anterior Rhine''' ({{langx|rm|Rein Anteriur}}, {{langx|de|Vorderrhein}}) springs from ''Lai da Tuma/Tomasee'', near the [[Oberalp Pass]] and passes the impressive ''[[Ruinaulta]]'' formed by the largest visible rock slide in the alps, the [[Flims Rockslide]].

:The '''Posterior Rhine''' ({{langx|rm|Rein Posteriur}}, {{langx|de|Hinterrhein}}) starts from the [[Paradies Glacier]], near the ''Rheinwaldhorn''. One of its tributaries, the ''Reno di Lei'', drains the ''[[Lago di Lei|Valle di Lei]]'' on politically Italian territory. After three main valleys separated by the two gorges, ''[[Roflaschlucht]]'' and ''[[Viamala]]'', it reaches [[Reichenau, Switzerland|Reichenau]] in [[Tamins]].
[[File:Karte Alpenrhein.png|thumb|upright=1.15|Map of the Alpine Rhine]]

The Anterior Rhine arises from numerous source streams in the upper [[Surselva]] and flows in an easterly direction. One source is ''[[Lake Toma|Lai da Tuma]]'' ({{convert|2345|m|abbr=on}})<ref>{{cite map |url=https://s.geo.admin.ch/790e465925 |title=Lai da Tuma |map=1232 - Oberalppass |map-url=https://shop.swisstopo.admin.ch/en/products/maps/national/lk25?layer=ch.swisstopo.landeskarte25_papier.metadata&product=1232&productIdentifier=1232&childGroupIdentifier=lk25eb#product-1232 |scale=1:25 000 |series=National Map 1:25'000 |edition=2015 |date=2013 |publisher=Federal Office of Topography – [[swisstopo]] |location=Wabern, Switzerland |isbn=978-3-302-01232-2 |via=map.geo.admin.ch |access-date=1 March 2018}}</ref> with the ''[[Rein da Tuma]]'', which is usually indicated as source of the Rhine, flowing through it.

Into it flow tributaries from the south, some longer, some equal in length, such as the ''Rein da Medel'', the ''[[Rein da Maighels]]'', and the ''[[Rein da Curnera]]''. The Cadlimo Valley in the [[canton of Ticino]] is drained by the ''Reno di Medel'', which crosses the [[geomorphology|geomorphologic]] Alpine main ridge from the south.{{notetag|The geomorphological ridge line does not necessarily coincide with the [[Drainage divide|watershed]], since it refers to the average altitude in a surrounding circle}} All streams in the source area are partially, sometimes completely, captured and sent to storage reservoirs for the local hydro-electric power plants.

The culminating point of the Anterior Rhine's drainage basin is the [[Piz Russein]] of the Tödi massif of the [[Glarus Alps]] at {{convert|3613|m|sp=us}} above sea level. It starts with the creek ''Aua da Russein'' (lit.: "Water of the Russein").<ref>{{cite map |url=http://s.geo.admin.ch/9324aa0f5 |title=Piz Russein |map=1193 - Tödi |map-url=https://shop.swisstopo.admin.ch/en/products/maps/national/lk25?layer=ch.swisstopo.landeskarte25_papier.metadata&product=1193&productIdentifier=1193&childGroupIdentifier=lk25eb#product-1193 |scale=1:25 000 |series=National Map 1:25'000 |edition=2016 |date=2013 |publisher=Federal Office of Topography – [[swisstopo]] |location=Wabern, Switzerland |isbn=978-3-302-01193-6 |via=map.geo.admin.ch |access-date=28 February 2018}}</ref>

In its lower course, the Anterior Rhine flows through a gorge named ''[[Ruinaulta]]'' (Flims Rockslide). The whole stretch of the Anterior Rhine to the Alpine Rhine confluence next to Reichenau in Tamins is accompanied by a long-distance hiking trail called ''Senda Sursilvana''.<ref>{{Cite news|url=https://maps.graubuenden.ch/de/tour/weitwanderweg/85-senda-sursilvana-5-etappen-/13223088/|title=85 Senda Sursilvana (5 Etappen)|website=maps.graubuenden.ch|access-date=14 November 2019|archive-date=6 January 2020|archive-url=https://web.archive.org/web/20200106225753/https://maps.graubuenden.ch/de/tour/weitwanderweg/85-senda-sursilvana-5-etappen-/13223088/|url-status=dead}}</ref>

The Posterior Rhine flows first east-northeast, then north. It flows through the three valleys named [[Rheinwald]], [[Schams]] and [[Domleschg valley|Domleschg]]-[[Heinzenberg GR|Heinzenberg]]. The valleys are separated by the [[Rofla Gorge]] and [[Viamala]] Gorge. Its sources are located in the [[Adula Alps]] ([[Rheinwaldhorn]], [[Rheinquellhorn]], and [[Güferhorn]]).

The [[Avers Rhine]] joins from the south. One of its headwaters, the ''Reno di Lei'' (stowed in the [[Lago di Lei]]), is partially located in Italy.

Near [[Sils im Domleschg|Sils]] the Posterior Rhine is joined by the [[Albula (river)|Albula]], from the east, from the [[Albula Pass]] region. The Albula draws its water mainly from the [[Landwasser]] with the [[Dischmabach]] as the largest source stream, but almost as much from the [[Gelgia (river)|Gelgia]], which comes down from the [[Julier Pass]].

Numerous larger and smaller tributary rivers bear the name of the ''Rhine'' or equivalent in various [[Romansch language|Romansh]] idioms, including ''Rein'' or ''Ragn'', including:
* Anterior Rhine area: ''Rein Anteriur/Vorderrhein'', ''[[Rein da Medel]]'', ''[[Rein da Tuma]]'', ''[[Rein da Curnera]]'', ''[[Rein da Maighels]]'', ''Rein da Cristallina'', ''Rein da Nalps'', ''Rein da Plattas'', ''Rein da Sumvitg'', ''Rein da Vigliuts'', ''[[Valser Rhine]]''
* Posterior Rhine basin: ''Rein Posteriur/Hinterrhein'', ''[[Lago di Lei|Reno di Lei]]'', ''Madrischer Rhein'', ''[[Avers Rhine]]'', ''Jufer Rhein''
* Albula-Landwasser area: In the [[Dischma]] valley, near Davos, far east of the Rhine, there's a place called ''Am Rin'' ("Upon Rhine"). A tributary of the Dischma is called ''Riner Tälli''. Nearby, on the other side of the [[Sertig]], is the ''Rinerhorn''.

===Alpine Rhine===
{{main|Alpine Rhine}}
[[File:Rhein bei Balzers - Blick auf Gonzen.JPG|thumb|The Rhine between [[Sargans]] in Switzerland (left) and [[Balzers]] in [[Liechtenstein]] (right) with the [[Gonzen]] ({{convert|1829|m|abbr=on}}, left), the [[Girrenspitz]] ({{convert|2099|m|abbr=on}}) in the back, and the Maziferchopf ({{convert|855|m|abbr=on}}) to the right]]
{{see also|Rheintal (disambiguation){{!}}Rheintal}}

Next to [[Reichenau, Switzerland|Reichenau]] in [[Tamins]] the [[Vorderrhein|Anterior Rhine]] and the [[Hinterrhein (river)|Posterior Rhine]] join and form the Alpine Rhine. The river makes a distinctive turn to the north near [[Chur]]. This section is nearly 86&nbsp;km long, and descends from a height of 599 meters to 396 meters. It flows through a wide glacial Alpine valley known as the Rhine Valley ({{langx|de|Rheintal}}). Near [[Sargan]] a natural dam, only a few meters high, prevents it from flowing into the open [[Sztal]] valley and then through [[Lake Walen]] and [[Lake Zurich]] into the [[Aare]]. The Alpine Rhine begins in the westernmost part of the Swiss canton of [[Graubünden]], and later forms the border between Switzerland to the west and Liechtenstein and later Austria to the east.

As an effect of human work, it empties into [[Lake Constance]] on Austrian territory and not on the [[Austria–Switzerland border|border]] that follows its old natural river bed called ''[[Alter Rhein]]'' ({{lit|Old Rhine}}).

The [[Rhine delta (Lake Constance)|mouth of the Rhine]] into Lake Constance forms an [[inland delta]]. The delta is delimited in the west by the ''Alter Rhein'' and in the east by the modern canalized section of the Alpine Rhine ({{lang|de|Fußacher Durchstich}}). Most of the delta is a [[nature reserve]] and [[bird sanctuary]]. It includes the Austrian towns of [[Gaißau]], [[Höchst, Austria|Höchst]] and [[Fußach]]. The natural Rhine originally branched into at least two arms and formed small islands by precipitating sediments. In the local [[Alemannic German|Alemannic]] dialect, the singular is pronounced "Isel" and this is also the local pronunciation of ''Esel'' ("[[Donkey]]"). Many local fields have an official name containing this element.

[[File:Aerial image of the mouth of the Rhine into Lake Constance.jpg|thumb|right|Aerial image of the mouth of the Rhine into [[Lake Constance]]]]
A [[Rhine Regulation|regulation of the Rhine]] was called for, with an upper canal near [[Diepoldsau]] and a lower canal at Fußach, in order to counteract the constant flooding and strong [[sedimentation]] in the western Rhine Delta. The [[Dornbirner Ach]] had to be diverted, too, and it now flows parallel to the canalized Rhine into the lake. Its water has a darker color than the Rhine; the latter's lighter suspended load comes from higher up the mountains. It is expected that the continuous input of sediment into the lake will silt up the lake. This has already happened to the former Lake [[Tuggenersee]].

The cut-off Old Rhine at first formed a [[swamp]] landscape. Later an artificial ditch of about two km was dug. It was made navigable to the Swiss town of [[Rheineck SG|Rheineck]].

=== Lake Constance ===
[[File:Bodensee satellit.jpg|thumb|right|upright=1.5|Satellite image. In the center and on the right (i.e. to the east) the larger part of Lake Constance, called the ''[[Obersee (Lake Constance)|Obersee]]'', is visible, and it includes, in the lower right, the [[River Delta|delta]] of the [[Alpine Rhine]]. The northwesterly "finger" (on the top left) is ''Lake Überlingen'', containing the island of [[Mainau]]. Below Lake Überlingen (also in the west) is the smaller ''[[Untersee (Lake Constance)|Untersee]]'', containing [[Reichenau Island]]. The Obersee and Untersee are connected by the four kilometers long [[Seerhein]]. On the left the [[High Rhine]] can be seen.]]
{{Main|Lake Constance}}
Lake Constance consists of three bodies of water: the [[Obersee (Lake Constance)|Obersee]] ("upper lake"), the [[Untersee (Lake Constance)|Untersee]] ("lower lake"), and a connecting stretch of the Rhine, called the Seerhein ("Lake Rhine"). The lake is situated in Germany, Switzerland and [[Austria]] near the Alps. Specifically, its shorelines lie in the German states of [[Bavaria]] and [[Baden-Württemberg]], the Austrian state of [[Vorarlberg]], and the Swiss cantons of [[Thurgau]] and [[St. Gallen]]. The Rhine flows into it from the south following the Swiss-Austrian border. It is located at approximately {{coord|47|39|N|9|19|E|type:waterbody}}.

==== Obersee ====
{{Main|Obersee (Lake Constance)}}
The flow of cold, grey mountain water continues for some distance into the lake. The cold water flows near the surface and at first does not mix with the warmer, green waters of Upper Lake. But then, at the so-called ''Rheinbrech'', the Rhine water abruptly falls into the depths because of the greater density of cold water. The flow reappears on the surface at the northern (German) shore of the lake, off the island of [[Lindau (Bodensee)|Lindau]]. The water then follows the northern shore until [[Hagnau am Bodensee]]. A small fraction of the flow is diverted off the island of [[Mainau]] into Lake Überlingen. Most of the water flows via the ''Constance hopper'' into the ''Rheinrinne'' ("Rhine Gutter") and Seerhein. Depending on the water level, this flow of the Rhine water is clearly visible along the entire length of the lake.

The Rhine carries very large amounts of debris into the lake{{snd}}over {{convert|3000000|m3|spell=in|abbr=out|sp=us}} annually.<ref>{{cite web |last1=Bergmeister |first1=U. |last2=Kalt |first2=L. |title=Geschiebeführung |trans-title=Conveyance of bedload |url=http://www.rheinregulierung.at/kms/cms/kms.php?id=21&str_id=22&det_back=1 |publisher=Internationale Rheinregulierung |archive-url=https://web.archive.org/web/20120322191124/http://www.rheinregulierung.at/kms/cms/kms.php?id=21&str_id=22&det_back=1 |archive-date=22 March 2012 |location=Lustenau |language=de |url-status=dead}}</ref> In the mouth region, it is therefore necessary to permanently remove gravel by dredging. The large [[sediment]] loads are partly due to the extensive [[land improvements]] upstream.

Three countries border the Obersee, namely Switzerland in the south, Austria in the southeast and the German states of [[Bavaria]] in the northeast and [[Baden-Württemberg]] in the north and northwest.

==== Seerhein ====
{{Main|Seerhein}}
[[File:Konstanz Blick vom Münsterturm.jpg|thumb|Distance markers along the Rhine indicate distances from this bridge in [[Konstanz]]]]
[[File:Rheinkilometer Loreley.JPG|thumb|right|upright|The 555&nbsp;km marker downstream from the [[Lorelei]]]]
The [[Seerhein]] is only {{Convert|4|km|mi|sp=us}} long. It connects the [[Obersee (Lake Constance)|Obersee]] with the 30&nbsp;cm lower [[Untersee (Lake Constance)|Untersee]]. Distance markers along the Rhine measure the distance from the bridge in the old city center of Konstanz.

For most of its length, the Seerhein forms the border between Germany and Switzerland. The exception is the old city center of Konstanz, on the Swiss side of the river.

The Seerhein emerged in the last thousands of years, when erosion caused the lake level to be lowered by about 10 meters. Previously, the two lakes formed a single lake, as the name still suggests.

==== Untersee ====
{{Main|Untersee (Lake Constance)}}
Like in the Obersee, the flow the Rhine can be traced in the Untersee. Here, too, the river water is hardly mixed with the lake water. The northern parts of the Untersee (Lake Zell and Gnadensee) remain virtually unaffected by the flow. The river traverses the southern, which, in isolation, is sometimes called ''Rhinesee'' ("Lake Rhine"). The ''[[Schweizerische Schifffahrtsgesellschaft Untersee und Rhein]]'' (URh) offers regular boat trips on Untersee.

Besides the ''Seerhein'', the [[Radolfzeller Aach]] is the main tributary of ''Untersee''. It adds large amounts of water from the [[Danube]] system to the ''Untersee'' via the [[Danube Sinkhole]].

Reichenau Island was formed at the same time as the Seerhein, when the water level fell to its current level.

Lake Untersee is part of the [[Germany–Switzerland border|border between Switzerland and Germany]], with Germany on the north bank and Switzerland on the south, except both sides are Swiss in [[Stein am Rhein]], where the [[High Rhine]] flows out of the lake.

===High Rhine===
{{Main|High Rhine}}
[[File:Karte Hochrhein.png|thumb|upright=1.35|The High Rhine]]
[[File:Rheinfall mit Rheinfallbrücke und Schloss Laufen.jpg|thumb|The Rhine Falls near [[Schaffhausen]] ([[Switzerland]])]]
The High Rhine ({{lang|de|Hochrhein}}) begins in [[Stein am Rhein]] at the western end of the Untersee. Now flowing generally westwards, it passes over the [[Rhine Falls]] ({{lang|de|Rheinfall}}) below [[Schaffhausen]] before being joined{{snd}}near [[Koblenz AG|Koblenz]] in the [[canton of Aargau]]{{snd}}by its major tributary, the [[Aare]]. The Aare more than doubles the Rhine's water discharge, to an average of slightly more than {{convert|1000|m3/s|abbr=on}},{{notetag|The fact that the Aare contributes the larger portion of the combined volume{{snd}}51.8%, based on 1961–1990 averages{{sfn|Schädler|Weingartner|2002|loc=Table 1, rows 10-10 and 20-10}}{{snd}}means that in hydrographical terms the Rhine could be considered a tributary of the Aare, but the greater length of the Alpine Rhine means that it retains the designation as main branch.}} and provides more than a fifth of the discharge at the Dutch border. The Aare also contains the waters from the {{convert|4274|m|abbr=on}} summit of [[Finsteraarhorn]], the highest point of the Rhine [[drainage basin|basin]].

Between [[Eglisau]] and [[Basel]], the vast majority of its length, the High Rhine forms the [[German-Swiss border|border between Germany and Switzerland]]. Only for brief distances at its extremities does the river run entirely within Switzerland; at the eastern end it separates the bulk of the [[cantons of Switzerland|canton]] of [[canton of Schaffhausen|Schaffhausen]] and the German [[exclave]] of [[Büsingen am Hochrhein]] on the northern bank from cantons of [[canton of Zürich|Zürich]] and [[Thurgau]], while at the western end it bisects the canton of [[Basel-Stadt]]. Here, at the [[Rhine knee]], the river turns north and leaves Switzerland altogether.

The High Rhine is characterized by numerous dams. On the few remaining natural sections, there are still several [[rapids]]. Over its entire course from Lake Constance to the Swiss border at Basel the river descends from {{cvt|395 to 252|m}}.

There are passenger boat lines on the lower High Rhine<ref>{{cite web |title=''Schifffahrt Rheinfelden – Basel'' [Boat trip Rheinfelden–Basel] |access-date=2025-02-08 |url=https://www.tourismus-rheinfelden.ch/en/experience/rhine-experience/shipping-rheinfelden-basel}}</ref> and [[Schweizerische Schifffahrtsgesellschaft Untersee und Rhein|between Schaffhausen and Kreuzlingen]].<ref>{{cite web |title=''Schifffahrtsgesellschaft Untersee und Rhein (URh)'' [Boat trip Schaffhausen–Kreuzlingen] |access-date=2025-02-08 |url=https://www.urh.ch/en/}}</ref>

=== Upper Rhine ===
{{Main | Upper Rhine}}
[[File:One autumn morning in Basel v2.jpg|thumb|The Rhine in [[Basel]] is Switzerland's gateway to the sea.]]
[[File:Rhein Mainzer Becken stromab von Mainz bei Eltville und Erbach vor Bingen Foto 2008 Wolfgang Pehlemann Wiesbaden IMG 0263.jpg|thumb|View of the Mainz Basin downstreams of Mainz, from Eltville and Erbach to Bingen]]
In the center of Basel, the first major city in the course of the stream, is the [[Rhine knee]], a major bend, where the overall direction of the Rhine changes from west to north. Here the High Rhine ends. Legally, the Central Bridge is the boundary between High and Upper Rhine. The river now flows north as Upper Rhine through the [[Upper Rhine Plain]], which is about 300&nbsp;km long and up to 40&nbsp;km wide. The most important tributaries in this area are the [[Ill (France)|Ill]] below of Strasbourg, the [[Neckar]] in Mannheim and the [[Main (river)|Main]] across from Mainz. In Mainz, the Rhine leaves the Upper Rhine Valley and flows through the Mainz Basin.
[[File:Fähre-Altrip Schiffe.jpg|thumb|The Rhine at [[Mannheim]], in the [[Rhine-Neckar]] industrial area]]
The southern half of the Upper Rhine forms the [[border]] between France ([[Alsace]]) and Germany (Baden-Württemberg). The northern part forms the border between the German states of [[Rhineland-Palatinate]] in the west on the one hand, and [[Baden-Württemberg]] and [[Hesse]] on the other hand, in the east and north. A curiosity of this border line is that the parts of the city of [[Mainz]] on the right bank of the Rhine were given to Hesse by the occupying forces in 1945.

The Upper Rhine was a significant cultural landscape in Central Europe already in [[Classical Antiquity|antiquity]] and during the [[Middle Ages]]. Today, the Upper Rhine area hosts many important manufacturing and service industries, particularly in the centers Basel, Strasbourg and Mannheim-Ludwigshafen. Strasbourg is the seat of the [[European Parliament]], and so one of the three European capitals is located on the Upper Rhine.

The Upper Rhine region was changed significantly by a Rhine straightening program in the 19th century. The rate of flow was increased and the ground water level fell significantly. Dead branches were removed by construction workers and the area around the river was made more habitable for humans on [[flood plains]] as the rate of flooding decreased sharply. On the French side, the [[Grand Canal d'Alsace]] was dug, which carries a significant part of the river water, and all of the traffic. In some places, there are large compensation pools, for example, the huge ''Bassin de compensation de [[Plobsheim]]'' in Alsace.

The Upper Rhine has undergone significant human change since the 19th century. While it was slightly modified during the Roman occupation, it was not until the emergence of engineers such as [[Johann Gottfried Tulla]] that significant modernization efforts changed the shape of the river. Earlier work under [[Frederick the Great]] surrounded efforts to ease shipping and construct dams to serve [[coal]] transportation.{{sfn|Cioc|2002|pp=48-49}} Tulla is considered to have domesticated the Upper Rhine, a domestication that served goals such as reducing stagnant [[bogs]] that fostered waterborne diseases, making regions more habitable for human settlement, and reduce high frequency of floods. Not long before Tulla went to work on widening and straightening the river, heavy floods caused significant loss of life.{{sfn|Cioc|2002|p=52}} Four diplomatic treaties were signed among German state governments and French regions dealing with the changes proposed along the Rhine, one was "the Treaty for the Rectification of the Rhine flow from Neuberg to Dettenheim"(1817), which surrounded states such as [[Bourbon France]] and the [[Bavarian Palatinate]]. Loops, [[Meander|oxbows]], branches and islands were removed along the Upper Rhine so that there would be uniformity to the river.{{sfn|Cioc|2002|p=53}} The engineering of the Rhine was not without protest, farmers and fishermen had grave concerns about valuable fishing areas and farmland being lost. While some areas lost ground, other areas saw swamps and bogs be drained and turned into arable land.{{sfn|Cioc|2002|p=54}} Johann Tulla had the goal of shortening and straightening the Upper Rhine. Early engineering projects the Upper Rhine also had issues, with Tulla's project at one part of the river creating rapids, after the Rhine cut down from erosion to sheer rock.{{sfn|Cioc|2002|p=54}} Engineering along the Rhine eased flooding and made transportation along the river less cumbersome. These state projects were part of the advanced and technical progress going on in the country alongside the industrial revolution. For the German state, making the river more predictable was to ensure development projects could easily commence.{{sfn|Cioc|2002|p=56}}

The section of the Upper Rhine downstream from [[Mainz]] is also known as the "Island Rhine". Here a number of [[river island]]s occur, locally known as "Rheinauen".

=== Middle Rhine ===
{{Main|Middle Rhine}}
[[File:RheinBeiRüdesheim2008Video.ogv|thumb|Rhine by ship from [[Assmannshausen]] to [[Rüdesheim am Rhein|Rüdesheim]], a 2008 video]] 
The Rhine is the longest river in Germany. It is here that the Rhine encounters some more of its main tributaries, such as the [[Neckar]], the [[Main (river)|Main]] and, later, the [[Moselle (river)|Moselle]], which contributes an average discharge of more than {{convert|300|m3/s|abbr=on}}. Northeastern France drains to the Rhine via the Moselle; smaller rivers drain the [[Vosges Mountains|Vosges]] and [[Jura Mountains]] uplands. Most of [[Luxembourg]] and a very small part of [[Belgium]] also drain to the Rhine via the Moselle. As it approaches the Dutch border, the Rhine has an annual mean discharge of {{convert|2290|m3/s|abbr=on}} and an average width of {{convert|400|m|abbr=on}}.

Between [[Bingen am Rhein]] and [[Bonn]], the [[Middle Rhine]] flows through the [[Rhine Gorge]], a formation which was created by [[erosion]]. The rate of erosion equaled the [[tectonic uplift|uplift]] in the region, such that the river was left at about its original level while the surrounding lands raised. The gorge is quite deep and is the stretch of the river which is known for its many castles and vineyards. It is a [[List of World Heritage Sites in Europe|UNESCO World Heritage Site (2002)]] and known as "the Romantic Rhine", with more than 40&nbsp;castles and fortresses from the [[Middle Ages]] and many quaint and lovely country villages.
{{gallery
|mode=packed
|height=150
|align=center
|File:FR-67-Strasbourg35.JPG|Between [[Strasbourg]] and [[Kehl]]
|File:Rhein stromabwärts bei Erbach im Rheingau mit Insel Mariannenau Hessen Landesgrenze Rheinland-Pfalz links - Foto Wolfgang Pehlemann Wiesbaden Photo IMG 0274.jpg|Aerial photo between [[Eltville]] and [[Bingen am Rhein|Bingen]]
|File:Marksburg1900.jpg|[[Marksburg]] near [[Koblenz]], built in 1231
|File:Beschädigte Brücke.jpg|[[Ludendorff Bridge]] at [[Remagen]], showing damage before collapse during the [[Battle of Remagen]]
|File:Cologne (Köln) Rhine River view b.jpg|The Rhine in [[Cologne]]
|File:Vue aérienne du Rhin à Dusseldorf.jpg|Rhine at [[Düsseldorf]]
|File:The Rhine Hünxe Germany .jpeg|Rhine at [[Hünxe]], near the border of the [[Netherlands]]
}}
The Mainz Basin ends in [[Bingen am Rhein]]; the Rhine continues as "Middle Rhine" into the [[Rhine Gorge]] in the [[Rhenish Slate Mountains]]. In this sections the river falls from 77.4&nbsp;m above sea level to 50.4&nbsp;m. On the left, is located the mountain ranges of [[Hunsrück]] and [[Eifel]], on the right [[Taunus]] and [[Westerwald]]. According to geologists, the characteristic narrow valley form was created by [[erosion]] by the river while the surrounding landscape was lifted (see [[water gap]]).

Major tributaries in this section are the [[Lahn]] and the [[Moselle]]. They join the Rhine near [[Koblenz]], for the right and left respectively. Almost the entire length of the Middle Rhine runs in the German state of Rhineland-Palatinate.

The dominant economic sectors in the Middle Rhine area are [[viniculture]] and tourism. The [[Rhine Gorge]] between [[Rüdesheim am Rhein]] and [[Koblenz]] is listed as a UNESCO [[World Heritage Site]]. Near [[Sankt Goarshausen]], the Rhine flows around the famous rock [[Lorelei]]. With its outstanding architectural monuments, the slopes full of vines, settlements crowded on the narrow river banks and scores of castles lined up along the top of the steep slopes, the Middle Rhine Valley can be considered the epitome of the Rhine romanticism.

=== Lower Rhine ===
{{Main|Lower Rhine}}
[[File:River Rhein Düsseldorf Bird's eye view - Rathausufer vor histor. Altstadt - Rheinufer NRW Wolfgang Pehlemann DSCN1026.jpg|thumb|Low water in [[Düsseldorf]]]]
[[File:Emmerich am Rhein Osten.jpg|thumb|The Lower Rhine at [[Emmerich am Rhein|Emmerich]]]]

In [[Bonn]], where the [[Sieg (river)|Sieg]] flows into the Rhine, the Rhine enters the [[North German Plain]] and turns into the Lower Rhine. The Lower Rhine falls from 50&nbsp;m to 12&nbsp;m. The main tributaries on this stretch are the [[Ruhr]] and the [[Lippe]]. Like the Upper Rhine, the Lower Rhine used to [[meander]] until engineering created a solid river bed. Because the levees are some distance from the river, at high tide the Lower Rhine has more room for widening than the Upper Rhine.

The Lower Rhine flows through [[North Rhine-Westphalia]]. Its banks are usually heavily populated and industrialized, in particular the [[agglomerations]] [[Cologne]], Düsseldorf and [[Ruhr area]]. Here the Rhine flows through the largest conurbation in Germany, the [[Rhine-Ruhr]] region. One of the most important cities in this region is [[Duisburg]] with the largest [[river port]] in Europe (Duisport). The region downstream of Duisburg is more agricultural. In Wesel, 30&nbsp;km downstream of Duisburg, is located the western end of the second east–west shipping route, the Wesel-Datteln Canal, which runs parallel to the Lippe. Between [[Emmerich am Rhein|Emmerich]] and [[Cleves]] the [[Emmerich Rhine Bridge]], the longest suspension bridge in Germany, crosses the {{convert|400|m|ft|adj=mid|-wide|sp=us}} river. Near [[Krefeld]], the river crosses the [[Uerdingen line]], the line which separates the areas where [[Low German]] and [[High German]] are spoken. The Rhine River is crossed by several [[Ferry|ferries]], including the one between [[Bad Honnef]] and [[Rolandseck]], where the [[Lohfelderfähre]] district is situated.

Until the early 1980s, industry was a major source of water pollution. Although many plants and factories can be found along the Rhine up into [[Switzerland]], it is along the [[Lower Rhine]] that the bulk of them are concentrated, as the river passes the major cities of [[Cologne]], [[Düsseldorf]] and [[Duisburg]]. Duisburg is the home of Europe's largest inland port and functions as a hub to the sea ports of [[Rotterdam]], [[Antwerp]] and [[Amsterdam]]. The [[Ruhr (river)|Ruhr]], which joins the Rhine in Duisburg, is nowadays a clean river, thanks to a combination of stricter environmental controls, a transition from heavy industry to light industry and cleanup measures, such as the [[reforestation]] of [[slag heaps|Slag]] and [[Brownfield land|brownfields]]. The Ruhr currently provides the region with drinking water. It contributes {{convert|70|m3/s|abbr=on}} to the Rhine. Other rivers in the [[Ruhr Area]] include the [[Emscher]].

=== Delta ===
{{Main|Rhine–Meuse–Scheldt delta|Nether Rhine}}
[[File:Maas Delta1.jpg|thumb|The central and northern parts of the Rhine-Meuse delta]]
[[File:Abbinden der Maas von der Waal 1904 aus Hochwasserschutzgründen.gif|thumb | Changing the [[Meuse (river)|Meuse]] estuary in 1904: light blue old course, dark blue today's course]]
[[File:Map of the annual average discharge of Rhine and Maas 2000-2011 (EN).png|thumb|Map showing how the waters of the Rhine and Meuse rivers split into various branches of their combined delta]]

[[File:John Frostbrug.jpg|thumb|The [[Nederrijn]] at [[Arnhem]]]]
The Dutch name for Rhine is "Rijn". The Rhine turns west and enters the [[Netherlands]], where, together with the rivers [[Meuse (river)|Meuse]] and [[Scheldt]], it forms the extensive [[Rhine-Meuse-Scheldt delta]], with {{convert|25347|km2|mi2|abbr=on}} the largest [[river delta]] in Europe.<ref>{{cite encyclopedia |last1=Tockner |first1=K. |last2=Uehlinger |first2=U. |last3=Robinson |first3=C. T. |last4=Siber |first4=R. |last5=Tonolla |first5=D. |last6=Peter |first6=F. D.  |editor-last=Likens |editor-first=G. E. |encyclopedia=Encyclopedia of Inland Waters |title=European Rivers |date=2009 |publisher=Elsevier |volume=3 |location=Amsterdam |isbn=978-0-12-370630-0 |oclc=319211428 |doi=10.1016/B978-012370626-3.00044-2 |pages=366–377}}</ref> Crossing the border into the Netherlands at [[Spijk (Rijnwaarden)|Spijk]], close to [[Nijmegen]] and [[Arnhem]], the Rhine is at its widest, although the river then splits into three main [[distributary|distributaries]]: the [[Waal (river)|Waal]], [[Nederrijn]] ("Nether Rhine") and [[IJssel]].

From here, the situation becomes more complicated, as the Dutch name ''Rijn'' no longer coincides with the main flow of water. Two-thirds of the water flow volume of the Rhine flows farther west, through the Waal and then, via the [[Merwede]] and [[Nieuwe Merwede]] ([[De Biesbosch]]), merging with the Meuse, through the [[Hollands Diep]] and [[Haringvliet]] [[estuary|estuaries]], into the [[North Sea]]. The [[Beneden Merwede]] branches off, near [[Hardinxveld-Giessendam]] and continues as the [[Noord (river)|Noord]], to join the [[Lek (river)|Lek]], near the village of [[Kinderdijk]], to form the [[Nieuwe Maas]]; then flows past [[Rotterdam]] and continues via [[Het Scheur]] and the [[Nieuwe Waterweg]], to the North Sea. The [[Oude Maas]] branches off, near [[Dordrecht]], farther down rejoining the [[Nieuwe Maas]] to form [[Het Scheur]].

The other third of the water flows through the [[Pannerdens Kanaal]] and redistributes in the IJssel and Nederrijn. The IJssel branch carries one ninth of the water flow of the ''Rhine'' north into the [[IJsselmeer]] (a former bay), while the Nederrijn carries approximately two-ninths of the flow west along a route parallel to the Waal. However, at [[Wijk bij Duurstede]], the Nederrijn changes its name and becomes the [[Lek (river)|Lek]]. It flows farther west, to rejoin the [[Noord (river)|Noord]] into the [[Nieuwe Maas]] and to the North Sea.

The name ''Rijn'', from here on, is used only for smaller streams farther to the north, which together formed the main river Rhine in [[Roman Empire|Roman]] times. Though they retained the name, these streams no longer carry water from the Rhine, but are used for draining the surrounding land and [[polder]]s. From Wijk bij Duurstede, the old north branch of the Rhine is called [[Kromme Rijn]] ("Bent Rhine") past [[Utrecht (city)|Utrecht]], first [[Leidse Rijn]] ("Rhine of [[Leiden]]") and then, [[Oude Rijn (Utrecht and South Holland)|Oude Rijn]] ("Old Rhine"). The latter flows west into a [[sluice]] at [[Katwijk]], where its waters can be discharged into the [[North Sea]]. This branch once formed the line along which the [[Limes Germanicus]] were built. During periods of lower sea levels within the various ice ages, the Rhine took a left turn, creating the [[Channel River]], the course of which now lies below the English Channel.

The Rhine-Meuse Delta, the most important [[natural region]] of the [[Netherlands]] begins near [[Millingen aan de Rijn]], close to the Dutch-German border with the division of the Rhine into [[Waal (river)|Waal]] and [[Nederrijn]]. The region between the Dutch-German border and Rotterdam, where the Waal, Lek, and Meuse run more or less parallel, is colloquially known as the "Great Rivers". Since the Rhine contributes most of the water, the shorter term ''Rhine Delta'' is commonly used. However, this name is also used for the [[river delta]] where the Rhine flows into [[Lake Constance]], so it is clearer to call the larger one ''Rhine-Meuse delta'', or even ''[[Rhine–Meuse–Scheldt delta]]'', as the Scheldt ends in the same delta.

The shape of the Rhine delta is determined by two [[River bifurcation|bifurcation]]s: first, at [[Millingen aan de Rijn]], the Rhine splits into [[Waal (river)|Waal]] and [[Pannerdens Kanaal]], which changes its name to [[Nederrijn]] at [[Angeren]], and second near [[Arnhem]], the [[IJssel]] branches off from the Nederrijn. This creates three main flows, two of which change names rather often. The largest and southern main branch begins as Waal and continues as [[Boven Merwede]] ("Upper Merwede"), [[Beneden Merwede]] ("Lower Merwede"), [[Noord (river)|Noord]] ("the North"), [[Nieuwe Maas]] ("New Meuse"), [[Het Scheur]] ("the Rip") and [[Nieuwe Waterweg]] ("New Waterway"). The middle flow begins as [[Nederrijn]], then changes into [[Lek (river)|Lek]], then joins the Noord, thereby forming Nieuwe Maas. The northern flow keeps the name IJssel until it flows into Lake [[IJsselmeer]]. Three more flows carry significant amounts of water: the [[Nieuwe Merwede]] ("New Merwede"), which branches off from the southern branch where it changes from Boven to Beneden Merwede; the [[Oude Maas]] ("Old Meuse"), which branches off from the southern branch where it changes from Beneden Merwede into Noord, and [[Dordtse Kil]], which branches off from Oude Maas.

Before the [[St. Elizabeth's flood (1421)]], the [[Meuse (river)|Meuse]] flowed just south of today's line Merwede-Oude Maas to the North Sea and formed an [[archipelago]]-like estuary with Waal and Lek. This system of numerous bays, estuary-like extended rivers, many islands and constant changes of the coastline, is hard to imagine today. From 1421 to 1904, the Meuse and Waal merged further upstream at [[Gorinchem]] to form [[Merwede]]. For flood protection reasons, the Meuse was separated from the Waal through a lock and diverted into a new outlet called "[[Bergse Maas]]", then [[Amer (river)|Amer]] and then flows into the former bay Hollands Diep.

The northwestern part of the estuary (around [[Hook of Holland]]), is still called ''Maasmond'' ("Meuse Mouth"), ignoring the fact that it now carries only water from the Rhine. This might explain the confusing naming of the various branches.

The hydrography of the current delta is characterized by the delta's main arms, disconnected arms ([[Hollandse IJssel]], [[Linge]], [[Vecht (Utrecht)|Vecht]], etc.) and smaller rivers and streams. Many rivers have been closed ("dammed") and now serve as drainage channels for the numerous [[polders]]. The construction of [[Delta Works]] changed the Delta in the second half of the 20th century fundamentally. Currently Rhine water runs into the sea, or into former marine bays now separated from the sea, in five places, namely at the mouths of the Nieuwe Merwede, Nieuwe Waterway (Nieuwe Maas), Dordtse Kil, [[Spui (river)|Spui]] and IJssel.

The Rhine-Meuse Delta is a tidal delta, shaped not only by the [[sedimentation]] of the rivers, but also by tidal currents. This meant that high tide formed a serious risk because strong tidal currents could tear huge areas of land into the sea. Before the construction of the Delta Works, tidal influence was palpable up to Nijmegen, and even today, after the regulatory action of the Delta Works, the [[tide]] acts far inland. At the Waal, the most landward tidal influence can be detected between [[Brakel, Gelderland|Brakel]] and [[Zaltbommel]].