Although they're convenient, Edgartown's in-town beaches are just kids' stuff. For the real deal head to Katama Beach, aka South Beach, about 3 miles south of Edgartown center. Kept in a natural state, this barrier beach stretches for three magnificent miles. Rugged surf will please surfers on the ocean side; many swimmers prefer the protected salt ponds on the inland side.
There's a bike path connecting Edgartown with Katama Beach – excellent for avoiding parking hassles.