Open water swimming is basically what it sounds like: you swim in the open water, such as the ocean, a river or a lake. One leg of a triathlon is typically an open water swim race, which looks like hundreds of people racing for the shore after someone hollers, “Shark!” Some open water swimmers take competition way beyond anything faced by a triathlete. The sport of marathon swimming involves open water races more than 10 km in length. Some are even longer.
5 Manhattan Island Marathon Swim, U.S.A.
One of the most popular long-distance, open water swim races, the Manhattan Island Marathon Swim is a 28.5 mile—nearly 46 km—circumnavigation of Manhattan. As the longest leg of the Triple Crown of Open Water Swimming—the English Channel and Catalina Channel are the two shorter swims—the Manhattan allows multiple types of competition, including solo as well as two- and three-person relay teams.
4 Maraton Acuatico Rio Santa Fe – Coronda, Argentina
Argentina is host to another of the five longest open water races in the world: the Maraton Acuatico Rio Santa Fe – Coronda, which is held on the Coronda River. Like the longer Hernandarias race, the 57 km, or 35.4 mi., Coronda swim is part of the FINA Open Water Swimming Grand Prix series.
3 Reto Vuelta a Nado Isla de Ibiza, Spain
A five-stage competition that sends you on a circumnavigation of Ibiza, a Mediterranean island off the Spanish coast, the Reto Vuelta a Nado Isla de Ibiza is 70 km, or 43.5 mi., in total distance. Each leg of the race begins and ends at one of the island’s renowned beaches. Presumably, the swimmers will be too exhausted after a 14 km swim to indulge in Ibiza’s infamous nightlife at the end of each day—but after the race is over, a foam party may be in order.
2 Maratón Acuatico Internacional Hernandarias – Paraná, Argentina
Coming in at 88 km, or more than 50 miles, Argentina’s Maratón Acuatico Internacional Hernandarias – Paraná is the longest single-leg open water race in the world. First held in 1965, the marathon occurs at irregular intervals. At times more than five years elapsed between races. However, in 2012 and 2013, the race was held in consecutive years, serving in 2013 as the Open Water Swimming Grand Prix event for the Federation Internationale de Natation, or FINA.
1 Eight Bridges Hudson River Swim, U.S.A.
Held in New York on the eponymous river, the longest, organized, open water swim race is the 8 Bridges Hudson River Swim. At 193 km—about 120 miles—the race is more than twice the distance of the next longest competition. However, unlike other open water marathon races, the 8 Bridges swim is completed in stages over a period of seven days. Each leg comes in at just over 25 km, which is a still a pretty impressive swim. Overall, the race makes for the most grueling week in open water swimming.