Find out everything you need to know about the 10km swimming marathon at London 2012 - from the rules of the sport, to the venue it will feature in, to the equipment required.
British Swimming is working with the BBC to get the UK into the pool in a celebration of swimming called the Big Splash. A wide range of activities, including competitive races, swimming lessons and aqua aerobics, are being put on in swimming pools throughout the country.
Visit the London 2012 schedule and results page on the BBC Sport website to find out details of when the Olympic swimming events are taking place, and where you can watch them.
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