The world's largest open water swimming event held at the Midmar Dam north of Pietermaritzburg, South Africa. Each year, it draws thousands of competitors, from serious international athletes and Olympic medallists to purely recreational swimmers. Named for the location, Midmar Dam and the distance which is roughly one mile. A unique feature of the race is that while the distance covered is always a mile, depending on rainfall and the water levels in the dam, the distance swum varies from year to year. In years with poor rainfall, competitors are subject to the infamous Midmar sprint start - a bedlam of bodies sprinting across the muddy lake-shore and through the shallows until the water is deep enough to swim. In order to handle the vast number of competitors, the swimmers strike out in several groups at two-minute intervals in eight batches over two days; the group division is based on a qualifying time in a previous event, with the fastest group leaving first.

Funky fact Who would have thought that petrol restrictions in 1973 would initiate the events that eventually led to the first ever Midmar Mile swim on Sunday 10 February 1974? Mike Arbuthnot, Dick Park and Brian Glover were unable to travel as far as East London to compete in the Buffalo Mile in 1973 due to the restrictions and they decided that a similar race be organised in Natal. Midmar Dam was chosen as the venue, which certainly has proved a popular choice. 153 swimmers entered the inaugural race in 1974 with the youngest competitor being 10 years old.