Providencia's beaches are lovely but secondary to its reef. The best stretches of sand are on the western side of the island, sheltered from the prevailing winds.
Manzanillo beach is the most visited — a calm bay with shallow water good for swimming, backed by a few small restaurants and palms. Aguadulce (Southwest Bay) is slightly longer and has some snorkelling close to shore. Both are accessible by moto-taxi or bicycle.
The east coast is more exposed and rougher, but worth visiting for the dramatic views of the reef breaking offshore. South West Bay is a good spot to watch sunsets. Avoid beaches on the northern tip in rough weather — waves can come in unexpectedly.
Note: jellyfish are occasionally a problem in the sheltered bays, particularly after heavy rains. Ask locals before swimming.