36 BC: Japanese organize the first known swimming races.

Ancient Rome: Swimming races are held in the Tiber River.

Middle Ages: Swimming with armor is one of seven agilities required of knights.

1844: Native Americans, swimming freestyle, upset the favored British, using breaststroke in well-publicized swim races in London.

1875: Captain Webb swims the English Channel, giving notoriety to long-distance swimming. No other person successfully swims the English Channel for 31 more years.

1896: Athens Olympics: Four swim races are held in the Bay of Zea (100, 500 and 1200 meters and a race for Greek sailors) in 55ºF water and very heavy surf.

1900 Paris Olympics: Five downstream swim races are held in the Seine River, including a 4K freestyle race won in under an hour.

1916: Annual La Jolla Roughwater Swim starts in San Diego.

1926: Gertrude Ederle becomes the first women to swim across the English Channel.

1927: George Young wins $50,000 in a Catalina Channel race, called the Wrigley Ocean Marathon. Ed Keating wins a 24-mile Lake George Swimming Marathon.

1954: The Around-the-Island pro swim race begins in Atlantic City. Pro swims in Canada, Atlantic City and the Great Lakes attract swimmers from the world.

1974: John Kinsella, Olympic gold and silver medalist, wins the first of several World Professional Marathon Swimming Federation circuit races. Paul Asmuth continues the American domination of professional marathon swimming throughout the 1980s.

1987: Lynne Cox swims across the Bering Strait in the Arctic Ocean. She later swims in Antarctica.

1990s: A global World Cup and Grand Prix Open Water pro series is organized by FINA. Americans Chad Hundeby, Tobie Smith and Erica Rose win world championships throughout the 1990s.

2006: The International Olympic Committee adds a 10K open water race to the 2008 Beijing Olympics.

August 20-21, 2008: The first Olympic medals will be awarded to the men’s and women’s 10K race in the Olympic rowing basin.