Editing Lake Constance (section)

==Description==
Lake Constance is located along the [[Rhine]] between the [[Alpine Rhine]], its main [[tributary]], and the [[High Rhine]], its outflow. It is the [[List of largest lakes of Europe|third largest]] freshwater lake by surface area in Central and Western Europe (and the second largest in volume), after [[Lake Geneva]] and (in surface area) [[Lake Balaton]].

It is {{convert|63|km|abbr=on}} long, and, nearly {{convert|14|km|abbr=on}} at its widest point. It covers about {{convert|536|km2|abbr=on}}, and is {{convert|395|m|abbr=on}} above [[sea level]]. Its greatest depth is {{convert|252|m}}, exactly in the middle of the Upper Lake. Its volume is about {{convert|48|km3|abbr=on}}.<ref name=data>{{cite web |url=https://www.igkb.org/der-bodensee/seedaten/ |title=Bodensee-Daten |publisher=igkb Internationale Gewässerschutzkommission für den Bodensee |date=June 2004 |language=de |access-date=2018-02-28 |archive-date=1 March 2018 |archive-url=https://web.archive.org/web/20180301104135/https://www.igkb.org/der-bodensee/seedaten/ |url-status=dead }}</ref>

The lake has two parts. The main east section, called [[Obersee (Lake Constance)|Obersee]] or "Upper Lake", covers about {{convert|473|km2}}, including its northwestern arm, the [[Überlinger See]] ({{convert|61|km2|abbr=on}}), and the smaller west section, called [[Untersee (Lake Constance)|Untersee]] or "Lower Lake", with an area of about {{convert|63|km2}}.<ref name=data/><ref name=mapGPBW1/>

The connection between these two lakes is the [[Seerhein]] (lit.: "Rhine of the Lake(s)"). Geographically, usually it is not considered to be part of the lake, but a very short river.<ref name=data/><ref name=map28/>

The Lower Lake Constance is loosely divided into three sections around the [[Island of Reichenau]]. The two German parts, the [[Gnadensee]] (lit.: "Lake Mercy") north of the island and north of the peninsula of Mettnau (the [[Markelfinger Winkel]]), and the [[Zeller See (Lake Constance)|Zeller See]], south of Radolfzell and to the northwest of the Reichenau island, and the mainly Swiss [[Rheinsee]] (lit.: "Lake Rhine") – not to be mistaken for the ''Seerhein'' (lit.: "Rhine of the Lake(s)") at its start – to the south of the island and with its southwestern arm leading to its effluent in [[Stein am Rhein]].<ref name=data/><ref name=mapGPBW1/>

The water of the [[Rhine Regulation|regulated]] Alpine Rhine flows into the lake in the southeast near [[Bregenz]], Austria, then through the Upper Lake Constance hardly targeting the ''Überlinger See'', into the ''Seerhein'' in the town of [[Konstanz]], then through the ''Rheinsee'' virtually without feeding both German parts of the Lower Lake, and finally feeds the start of the [[High Rhine]] in Swiss town [[Stein am Rhein]].<ref name=data/><ref name=map28bis/><ref name=mapGPBW1/>

The lake itself is an important source of drinking water for southwestern Germany.

The culminating point of the lake's drainage basin is the Swiss peak [[Piz Russein]] of the Tödi massif of the [[Glarus Alps]] at {{convert|3613|m}} 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=2018-02-28}}</ref>