River Thames to the strong current of the river, but also other river users. Organised swimming events take place at various points generally upstream of Hampton Court, including Windsor, Marlow and Henley. In 2011 comedian David Walliams swam the from Lechlade to Westminster Bridge and raised over £1 million for charity. In non-tidal stretches swimming was, and still is, a leisure and fitness activity among experienced swimmers where safe, deeper outer channels are used in times of low stream. A Thames meander is a long-distance journey over all or part of the Thames by running, swimming or using any of the above
River Thames with the establishment of regattas such as Henley and the Boat Race. On 3 September 1878, one of the worst river disasters in England took place, when the crowded pleasure boat collided with the "Bywell Castle", killing over 640 people. The growth of road transport, and the decline of the Empire in the years following 1914, reduced the economic prominence of the river. During the Second World War, the protection of certain Thames-side facilities, particularly docks and water treatment plants, was crucial to the munitions and water supply of the country. The river's defences included the Maunsell forts in the