More than 100 swimmers will take on one of Long Island’s most iconic endurance events Friday morning as the Maggie Fischer Great South Bay Cross Bay Swim celebrates a major milestone, its 100th anniversary.

The annual swim stretches 5.5 miles across the Great South Bay, beginning near the Fire Island Lighthouse and ending at Gilbert Park in Brightwaters. This year, 115 swimmers are participating. They will board a ferry before sunrise, with the race officially beginning at 7 a.m.

The Cross Bay Swim has raised millions of dollars over the years to support local charities and continues a century-long tradition of bringing together athletes, volunteers, and spectators.