Best for Learning to Swim
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Crescent Beach, Rhode Island

At the southern end of Block Island's Crescent Beach, a stretch of sand suits young families so well that the locals call it Baby Beach. Here toddlers wade in shallow tide pools, discovering mussels, crabs, and sand dollars while their parents recover on the crowdless sands. As a bonus, you don't have to worry about traffic: At the ferry, bike rentals with optional trailers or child seats are available for the short ride to Baby Beach, only three quarters of a mile away.