Miami resident Yoelvis Pedraza, 31, emerged from the Atlantic Ocean as the top individual swimmer with a time of 2 hours, 55 minutes and 36 seconds.
Top female finisher Chelsea Nauta, 29, of Tampa, completed the race in 3:04:21.
In other divisions, Tampa residents Pam Owens and Connor Signorin finished with the fastest two-person relay time of 3:28:57. Punta Gorda, Florida., residents Danielle Chance and Melissa Varlas teamed up with Laura Hamel and Rick Walker of Sarasota, Florida, in the four-person mixed relay division to place first with 3:33:46.
Athletes swam to Alligator Reef Lighthouse off Islamorada, rounded the beacon and came back to the start and finish points at Amara Cay Resort.
The annual event, conceived to raise awareness of preserving the 145-year-old Alligator Reef Lighthouse and five other aging lighthouses off the Florida Keys, raises college scholarship funds for Keys students interested in competitive swimming.