Acqua alta pronunciation (help·info) (Italian: 'high water') is the term used in Veneto for the exceptional tide peaks that occur periodically in the northern Adriatic Sea. The peaks reach their maximum in the Venetian Lagoon, where they cause partial flooding of Venice and Chioggia; flooding also occurs elsewhere around the northern Adriatic, for instance at Grado and Trieste, but much less often and to a lesser degree. The phenomenon occurs mainly between autumn and spring, when the astronomical tides are reinforced by the prevailing seasonal winds which hamper the usual reflux. The main winds involved are the scirocco, which blows northbound along the Adriatic Sea, and the bora, which has a specific local effect due to the shape and location of the Venetian lagoon.
Venice (Italian: Venezia [veˈnɛttsja] ( listen), Venetian: Venexia [veˈnɛsja]; (Latin: Venetia)) is a city in northeastern Italy sited on a group of 118 small islands separated by canals and linked by bridges. It is located in the marshy Venetian Lagoon which stretches along the shoreline between the mouths of the Po and the Piave Rivers. Venice is renowned for the beauty of its setting, its architecture and its artworks. The city in its entirety is listed as a World Heritage Site, along with its lagoon.
Venice is the capital of the Veneto region. In 2009, there were 270,098 people residing in Venice's comune (the population estimate of 272,000 inhabitants includes the population of the whole Comune of Venezia; around 60,000 in the historic city of Venice (Centro storico); 176,000 in Terraferma (the Mainland), mostly in the large frazioni of Mestre and Marghera; 31,000 live on other islands in the lagoon). Together with Padua and Treviso, the city is included in the Padua-Treviso-Venice Metropolitan Area (PATREVE), with a total population of 1,600,000. PATREVE is only a statistical metropolitan area without any degree of autonomy.