Longest distance open water swimming in relay

The longest distance swimming in relay in open water by an unlimited team is 684.75 km (425.48 miles) and was achieved by a group of 200 swimmers at Lake Camlough, Camlough, Northern Ireland, United Kingdom, between 9 to 19 September 2009. In total over 200 swimmers took part in swimming around a 750 m circuit. Gavin Brown swam the Farthest distance in one leg, completing five laps (3,750 m) in 1 hr 04 min 34 sec. The event was organised by Padraig Mallon.