Donauinsel

The Donauinsel (Danube Island) is a long, narrow island in central Vienna, Austria, lying between the Danube river and the parallel excavated channel Neue Donau ("New Danube"). The island is 21.1 km (13.1 mi) in length, but is only 70–120 m (230–394 ft) wide. The New Danube waterway is practically an elongated (swimming) lake, technically a diluvian bed.

To most visitors, the island is known as a recreational area with bars, restaurants and nightclubs. It has sports opportunities from rollerblading, cycling and swimming to canoeing. There is one beach that, in its beginning, felt so exotic that it was soon nicknamed the "Copa Cagrana" as a humoristic allusion to Rio de Janeiro's Copacabana: Kagran is the part of the 22nd District of Vienna next to that beach. In the southern and northern parts of the island, there are extensive (and free) nude beaches.

The Donauinselfest is an internationally well-known annual open air festival, and Europe's biggest event of this kind, with over 3 million visitors. It takes place at the end of June (Friday through Sunday) – except for 2008 (September 5–7), due to Austria (and Switzerland) hosting the European Football Championship. On September 23, 2008, Madonna gave her first concert in Austria there in front of a crowd of 57,000.

The main purpose of the island however is to be part of Vienna's highly sophisticated flood protection system. As the river Danube crosses the city (before major extensions: passed nearby), this has been a constant concern over hundreds of years. The first notable protective measures were taken between 1870 and 1875. A central bed, 280 m, was dug out, and an inundation area of 450 m was created at the river's left bank.

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