Editing Geography of Italy (section)

==Hydrography==
Italy is surrounded, except to the north, by the sea, and its territory has a rich reserve of inland waters (rivers and lakes). The southern regions, however, are drier than the northern ones, due to the scarcity of rains and the absence of glaciers that can feed the rivers.

===Rivers===
[[File:Torino-mole11.jpg|thumb|The [[Po river|Po]] river in [[Turin]]]]
[[File:Roma-tevere.jpg|thumb|The [[Tiber]] river in [[Rome]]]]
Italian [[river]]s are shorter than those of other European regions due to the Apennines that run along the entire length of the peninsula, dividing the waters into two opposite sides. They are numerous however, due to the relative abundance of rains in Italy in general, and to the presence of the Alpine chain, rich in snowfields and glaciers, in northern Italy.

The fundamental [[Drainage divide|watershed]] follows the ridge of the Alps and the Apennines and defines five main slopes, corresponding to the seas into which the rivers flow: the Adriatic, Ionic, Tyrrhenian, Ligurian and Mediterranean sides.<ref name=FIUMI>{{cite book|first=Antonio|last=Londrillo|title=Alla scoperta della mia regione|publisher=Bulgarini|year=2004|isbn=88-234-2327-9|language=it|page=26}}</ref> Italian rivers are categorized into two main groups: the Alpine-Po river rivers and the Apennine-island rivers.<ref name=FIUMI />

The longest Italian river is the [[Po river|Po]] ({{cvt|652|km|disp=or}}), which flows from the [[Monviso]], runs through the entire [[Po Valley]] from west to east, and then flows, with a [[River delta|delta]], into the [[Adriatic Sea]]. In addition to being the longest, it is also the river with the largest basin and the largest flow at its mouth. The second longest Italian river is the [[Adige]] ({{cvt|410|km|disp=or}}), which originates near [[Lake Resia]] and flows into the Adriatic Sea, after having made a north–south route, near [[Chioggia]]. The third longest river in Italy is the [[Tiber]] ({{cvt|405|km|disp=or}}), the second longest Italian river in terms of hydrographic basin; it was formed on [[Monte Fumaiolo]] (in [[Emilia-Romagna]]) and flows into the [[Tyrrhenian Sea]] after having crossed the center of [[Rome]]. After the Tiber, in order of length are the rivers [[Adda (river)|Adda]] ({{cvt|313|km|disp=or}}), [[Oglio]] ({{cvt|280|km|disp=or}}), [[Tanaro]] ({{cvt|276|km|disp=or}}) and [[Ticino (river)|Ticino]] ({{cvt|248|km}}, of which {{cvt|157|km}} is in Italy).

Most of Italy's rivers drain either into the Adriatic Sea (such as Po, [[Piave (river)|Piave]], [[Adige]], [[Brenta (river)|Brenta]], [[Tagliamento]], [[Reno River|Reno]]) or into the Tyrrhenian (like [[Arno]], [[Tiber]] and [[Volturno]]), though the waters from some border municipalities drain into the [[Black Sea]] through the basin of the [[Drava]] ([[Innichen]] and [[Sexten]] in [[Trentino-Alto Adige/Südtirol]], [[Tarvisio]] in [[Friuli-Venezia-Giulia]]) or the [[Inn (river)|Inn]] ([[Livigno]] in [[Lombardy]]), both [[tributary|tributaries]] of the [[Danube]], and the waters from the [[Lago di Lei]] in Lombardy drain into the [[North Sea]] through the basin of [[Rhine]].

===Lakes===
[[File:Altstadt von Malcesine-2.jpg|thumb|[[Lake Garda]] is the largest of the [[List of lakes in Italy|Italian lakes]]]]
In Italy there are more than 1,000 lakes, mostly artificially created by the damming of river valleys.<ref name=LAGHI>{{cite book|first=Antonio|last=Londrillo|title=Alla scoperta della mia regione|publisher=Bulgarini|year=2004|isbn=88-234-2327-9|language=it|page=28}}</ref>

In the north of the country are a number of subalpine [[moraine-dammed lake|moraine-dammed]] lakes (the [[Italian Lakes]]), including the largest in Italy, the [[Lake Garda|Garda]] ({{convert|370|km2|sqmi|0|abbr=on|disp=or}}).<ref name=Laghimari>{{cite book|first=Gianfranco|last=Bresich|title=Iperlibro|publisher=Deagostini|year=2005|isbn=88-418-2169-8|page=254|language=it}}</ref> Other well known of these subalpine lakes are [[Lake Maggiore]] ({{convert|212.5|km2|sqmi|0|abbr=on|disp=or}}), whose most northerly section is part of Switzerland, [[Como lake|Como]] (which holds the record of depth in the Italian Republic, which amounts to {{convert|410|m|abbr=on|disp=or}})<ref>{{cite book|title=Le Garzantine|year=2006|author=Various authors|chapter=Geografia: Ita-z|publisher=Garzanti Libri|language=it|page=781}}</ref> ({{convert|146|km2|sqmi|0|abbr=on|disp=or}}), [[Orta lake|Orta]], [[Lugano lake|Lugano]], [[Iseo lake|Iseo]], [[Idro lake|Idro]]. These lakes occupy wide valleys carved by ancient glaciers.

In Italy there are also coastal lakes, such as [[Lake Lesina]], separated from the sea by a narrow strip of land, and volcanic lakes ([[Lake Bolsena]], [[Lake Vico]], [[Lake Bracciano]]), which occupy the craters of extinct volcanoes. [[Lake Trasimeno]], on the other hand, formed in a hollow in the territory.<ref name=Laghimari /> Other notable lakes in the Italian peninsula are [[Lago di Varano|Varano]] and [[Lake Omodeo|Omodeo]] in [[Sardinia]].

The swamps and ponds that in the past covered vast flat areas of Italy, in recent centuries have been largely dried up;<ref name=Laghimari /> the few remaining wetlands, such as the [[Valli di Comacchio]] in Emilia-Romagna or the [[Stagno di Cagliari]] in Sardinia, are protected as very precious natural environments.<ref name=Laghimari />

Along the Italian coasts there are lagoons, among which the [[Venetian Lagoon]], that of [[Grado Lagoon]] and that of [[Marano Lagoon]] in the northern Adriatic stand out for their size and importance, and the [[Orbetello Lagoon]] on the Tuscan coast.

===Seas and coasts===
[[File:Strait of Messina from Dinnammare.jpg|thumb|View of the [[Strait of Messina]]]]
[[File:Urban-Rural Population and Land Area Estimates, v2, 2010 Northeast Italy (13873744025).jpg|thumb|Population density (''left'') and elevation above sea level (''right'') in [[Veneto]] (2010). Veneto is particularly vulnerable to rising [[sea level]].]]

The Italian peninsula overlooks the [[Mediterranean Sea]], which around it is divided into various seas.<ref name=Laghimari />

The [[Ligurian Sea]] bathes the coasts of [[Liguria]] and, according to the cartography of the Hydrographic Institute of the Navy, the northern Tuscan coasts to the south as far as the island of [[Elba]].

The [[Tyrrhenian Sea]] bathes the western coasts of the peninsula south of the island of Elba (and therefore all the regions from [[Tuscany]] to [[Calabria]]), the northern coasts of [[Sicily]] and the eastern coasts of [[Sardinia]].

The [[Adriatic Sea]] bathes the eastern coasts of the peninsula, from [[Friuli-Venezia Giulia]] to the Cape of [[Santa Maria di Leuca]], [[Apulia]].

The [[Ionian Sea]] bathes the eastern coasts of Sicily and Calabria, the coast of [[Basilicata]] and the western coasts of Apulia.

To the south of Sicily lies the [[Strait of Sicily]], while to the west of Sardinia lies the [[Sea of Sardinia]].<ref>{{Cite web|url=http://www.meteoam.it/modules/theory/bollettino/maremediterraneo.jpg|access-date=14 April 2010|title=Mappa con i bacini del Mediterraneo|language=it}}</ref>

Italy has a coastline of approximately {{cvt|7900|km}},<ref name=Coste>{{cite book|first=Antonio|last=Londrillo|title=Alla scoperta della mia regione|publisher=Bulgarini|year=2004|isbn=88-234-2327-9|language=it|page=32}}</ref><ref>{{Cite web|url=http://www.cngeologi.it/wp-content/uploads/2012/08/WWF_DOSSIERCOSTE_profilofragile_2012.pdf/|title=Copia archiviata|access-date=17 September 2019|archive-url=https://web.archive.org/web/20171204061313/http://www.cngeologi.it/wp-content/uploads/2012/08/WWF_DOSSIERCOSTE_profilofragile_2012.pdf|url-status=dead|language=it|archive-date=4 December 2017}}</ref> with a great variety of shapes that depends both on the nature of the mainland and on the action of the sea.

The Adriatic coasts are quite straight, characterized to the north by the gulfs of [[Trieste]] and [[Venice]], in the center by the [[Monte Conero|Conero]] promontory, to the south by that of the [[Gargano]], which forms the [[Gulf of Manfredonia]]. The Adriatic coasts are low and sandy,<ref name=Laghimari /> with lagoons in the northern section. Only in the Trieste area, in correspondence with the Gargano, the Conero and the lower eastern [[Salento]] (between [[Otranto]] and [[Santa Maria di Leuca]]) do rocky sections follow one another.

The Ionian coasts are mainly low and sandy and are characterized by the wide [[Gulf of Taranto]], closed to the east by the Salento Peninsula (which divides it from the Adriatic) and to the west by the Calabrian peninsula (which divides it from the Tyrrhenian Sea).

The [[Strait of Messina]] connects the Ionian and the Tyrrhenian seas.

The Tyrrhenian coasts are very articulated, with rocky stretches alternating with sandy beaches, with numerous gulfs and headlands. Among the many gulfs include [[Naples]], [[Salerno]] and [[Gaeta]], between the peninsulas that of [[Sorrento]] and the promontories that of [[Circeo]] and that of [[Piombino]]. In the Tyrrhenian Sea, there are three important channels: between the island of Elba and the Tuscan coast the [[Strait of Piombino]], between Elba and Corsica the [[Strait of Corsica]],<ref name=Laghimari /> and between Sardinia and Corsica the [[Strait of Bonifacio]].

The Ligurian Sea, which has the [[Gulf of Genoa]] at its center, has high and rocky coasts in the [[Riviera di Levante]] and mixed coasts in the [[Riviera di Ponente]].<ref name=Laghimari />