Open-Water Swimming
Long-distance swimming in seas, lakes and rivers — Olympic 10 km "marathon swim" and legendary channel crossings.
👥1 per team🌤outdoor
What is Open-Water Swimming?
Open-water swimming covers long-distance swimming in lakes, rivers and seas. The Olympic "marathon swim" is a 10 km mass-start race; the international pro circuit includes 25 km world championship events and multi-day marathon races. The English Channel (33 km), Catalina Channel and Manhattan Island form the sport's classic Triple Crown.
Quick facts
Category
Aquatic Sports
Type
Individual
Players
1 per team
Where played
outdoor
Country of origin
🇬🇧 United Kingdom
Estimated origin
1875, Matthew Webb's English Channel crossing; Olympic 10 km since Beijing 2008
Olympic
Yes
Popularity
global
Sources & provenance
Last verified 2026-08-24.verified