Diana Nyad, a 64-year-old endurance swimmer, became the first person to swim to Florida from Cuba without a shark cage.
The swimmer said this would be her last attempt to cover the distance after failing to complete the swim three times in 2011 and 2012, and once in 1978.
Nyad, whose last attempt was shortened by jellyfish stings, wore a full bodysuit, gloves, booties and a night mask to help prevent a repeat.
Australian Susie Maroney became the first person to cover the distance across the Florida Straits on May 12, 1997. She used a shark cage which has a drafting effect that pulls a swimmer along in addition to giving protection from the sharks, the Associated Press said.
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