A marathon swim is a nonstop, unassisted open water swim of 10 kilometers or longer.
Marathon swims take place in oceans, seas, bays, lakes, and rivers throughout the world - as part of organized events, sanctioned solo swims, or self-organized independent solo swims.
MSF Documented Swims
For publishing and ratifying documentation of independent marathon swims (not part of an organized race or governed by a local association).
Go to: MSF Documented Swims
- Documentation requirements
- Standard observer log + Instructions (PDF)
- Ratified swims:
The world’s most comprehensive repository of solo marathon swim results, listing 70,000+ documented, unassisted swims, 1875 to present.
Swim Event Calendars
For a more extensive list of marathon swims, see MSF’s continuously-updated calendars of organized marathon swims:
- Toughest Thirteen
- Triple Crown of Open Water Swimming - English Channel, Catalina Channel, Swim Around Manhattan
- Oceans Seven - English Channel, Catalina Channel, Strait of Gibraltar, North Channel, Cook Strait, Kaiwi Channel, Tsugaru Strait.
- California Triple Crown - Catalina Channel, Santa Barbara Channel, Lake Tahoe.
- New Zealand Triple Crown - Cook Strait, Lake Taupo, Foveaux Strait.
- Australian Triple Crown - Port to Pub, Palm to Shelly, Derwent River Big Swim.