Marathon Swimming is defined by distance. Marathon Swims are categorised as anything equal to or greater than 10KM. There are hundreds of events worldwide for the marathon swimmer. Sea, rivers, lakes and lochs all host swimmers going the distance. Events can be mass participation of elite with many catering for both.
As an elite event, the 10KM event debuted at the Beijing Olympic Games 2008, where Britons Keri-Anne Payne, Cassie Pattern and David Davies medalled with silver, bronze and bronze respectively. Since Beijing the event has enjoyed great success in the Serpentine, Hyde Park for London 2012 and in the Atlantic for Rio 2016.
At 10KM, Marathon Swims are some of the longest and toughest events in the world.
Running has its standard marathon of 26.2 miles, cycling arguably has its marathon of 100 miles. Swimming's 10k, although the shortest in distance, is probably the most technically and physically demanding of all marathon events. Marathon swimming is also seeing a great increase in interest and participation in recent years. Some swim marathons exceed 10k.