Nyad was flanked by kayakers and a diver who kept an eye out for sharks during her journey. One diver had to be treated for a painful jellyfish sting less than 3 hours into the 103-mile swim.
Nyad's attempt to swim between Cuba and Florida last year ended after 41 hours in the water after she was stung by jellyfish.
The noted long-distance swimmer, who turns 63 Wednesday, once swam around the island of Manhattan (1975) and 102 miles from the Bahamas to Florida (1979).
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