Marathon swims are generally defined as non-stop swims in open bodies of water of at least 10 km (6.2 miles) in distance. This distance is accepted by the International Olympic Committee, FINA, many national swimming federations and the International Marathon Swimming Hall of Fame, although some define a marathon swimming distance as 15 miles, 25 km or 20 miles. It can also refer to Ultra marathon swims of distances greater than 10 kilometers.
The athletes were preparing for a 25-kilometer pro marathon swimming race.
1895–1900; allusion to Pheidippides’ 26-mi. (42-km) run from MARATHON to Athens to carry news of the Greek victory over the Persians in 490 b.c.] + [Origin: bef. 1000; ME; OE swimmende (adj.)]
A marathon run is defined as 26.2 miles or 42.195 km, but the definition of a marathon swim varies greatly. A marathon swim is defined by FINA 10 kilometers (6.2 miles) in length with the Olympic 10K Marathon Swim as its most visible race. Other examples around the world include the Atlantic City Around-the-Island Marathon Swim is 37 kilometers (22.5 miles), Tampa Bay Marathon Swim is 38.6 kilometers (24 miles), Manhattan Island Marathon Swim is 46 kilometers (28.5 miles), Maratona del Golfo Capri-Napoli in Italy is 36 kilometers, Maraton Acuatica Internacional Santa Fe – Coronda in Argentina is 57 kilometers, Sumidero Canyon Swimming Marathon in Mexico is 15 kilometers, Maratón Acuática Internactional Ciudad de Rosario in Argentina is 15 kilometers, Maraton Patagones Viedma in Argentina is 15 kilometers, Ohrid Lake Swim Marathon in Macedonia is 30 kilometers, Galata Varna Swimming Marathon is 4 kilometers, Self-Transcendence Marathon Swim is 26.4 kilometers, PT109 Commemorative Swim Marathon is a 5 kilometer swim in the Solomon Islands.
According to Ted Erikson, in the 1960′s, 16 kilometers (10 miles) was referred to as a marathon swim because of the relative times involved for completion. Wikipedia refers to marathon swimming as 10 kilometers in distance, referring to the FINA definition.
International Swimming Hall of Fame inductee Timothy Johnson describes a slew of marathon swims of various lengths in his authoritative book, History of Open Water Marathon Swimming. Conrad Wennerberg also provides a rich description of marathon swims in his book, Wind, Waves, and Sunburn: A Brief History of Marathon Swimming. The Canadian Encyclopedia defines marathon swimming as swimming in open water for distances in excess of 1500 meters. The Encyclopedia of New Zealand defines marathon swims as longer than 10 kilometers. The World Professional Marathon Swimming Federation was formed in 1963 by professional marathon swimmers; its shortest swim was 16 kilometers in length. Sports Illustrated has written about marathon swimming over the years. In one article, the magazine described one marathon swim by Diane Nyad as 10 miles in length. The International Marathon Swimming Hall of Fame defines marathon swimming as 25 kilometers.
A 10-kilometer swim done by a world-class swimmer is comparable in time to a marathon run done by world-class marathon runners.
The marathon run distance was standardized in 1921 after various distances had been debated since the 1st century AD. Swimmers are hopeful the marathon swimming community will come to an agreement in a shorter time frame than its running counterparts.
Marathon Swimming Events
In addition to the English Channel, North Channel, Catalina Channel, Molokai Channel, Tsugaru Channel, Cook Strait, Strait of Gibraltar and other channel swims or circumnavigations worldwide, below is a representative (but not exhaustive) list of marathon swimming competitions that are held annually around the world, compiled by Open Water Source: