Mermaiding Swimming Association: These folks are all about the mermaid life. According to the Mermaiding Swimming Association, the sport involves swimming with a monofin or mermaid tail and combines the techniques of finswimming, freediving, and synchronized swimming. The group spans the Atlantic, representing mermaiders in the U.S. and Europe.

World Open Water Swimming Association: Members of the World Open Water Swimming Association find pools shallow. WOWSA—as it prefers to be called—caters to people who are passionate about swimming in open waters, including lakes, rivers, and oceans. WOWSA members do everything from ice swimming to marathons.

College Swimming and Diving Coaches Association of America: Founded in 1922, the College Swimming and Diving Coaches Association of America is the oldest coaches association in the U.S. The group claims to have started the modern “spring break phenomenon,” saying the week sprang directly from CSCAA’s annual winter student training session in Florida.

[Editor’s Note: This story has been updated to reflect the preferred name of CSCAA.]

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