The Strandbad Wannsee is an open-air lido on the eastern shore of Großer Wannsee lake, a large bay of the Havel river in Berlin, Germany. Opened in 1907, it is one of the largest inland lidos in Europe, with a beach that is 1,275 metres (4,183 ft) long and 80 metres (260 ft) wide, replenished with sand from the Baltic coast. The entire ensemble of long, low buildings that appear to grow out of the underlying sandhills were designed by Richard Ermisch and fellow architect Martin Wagner in 1929–1930; it is today placed under monumental protection.
The area is part of the Nikolassee locality (not of Wannsee), in the Steglitz-Zehlendorf borough, in southwestern Berlin. The lido stretches along the northern section of the lake's east bank, at the eastern end of the Breite, the broad stretch of the Havel between Kladow and Wannsee, close to Schwanenwerder island.
Strandbad Wannsee is run as a municipal swimming bath by the City of Berlin. The premises cover about 355,000 m², 130,000 of which is water, and 60,000m² are for sunbathing, and a park. The facilities laid out for about 12,000 bathers provide the famous beach, including a separate nudist-section, numerous strandkorbs and deckchairs, a slide at the end of the shallower water area as well as playground, park and a promenade that was a prominent part of the historical plans for the establishment. On hot summer days, up to 30,000 visitors crowd on the grounds.
Origins of the lido date back to the early 1900s. The City of Berlin, German capital since the unification of 1871, experienced immense growth, both in population and in building. Large housing projects were planned and realized, cramping the working population close together in small flats, with little light and less fresh air. Consequently, people tried to escape when their life allowed. Preferred places of escape for those who could not afford to go on vacation to the Baltic Sea were the lakes in the vicinity. Especially suitable was the Greater Wannsee, with its broad and shallow, sandy eastern shore.