4 Best Sights in Ponce and the Porta Caribe, Puerto Rico

As soon as the sun sets, large and small boats line the dock to take visitors out to view the Bioluminescent Bay. Microscopic dinoflagellates glow when disturbed by movement, suffusing the waves with thousands of starlike points of light. The bay's glow has been diminished substantially by pollution—both light pollution from nearby communities and water pollution from toxic chemicals dumped into the bay and constant boat traffic. This bay isn't as bright as the one in Vieques, but it's the only swimmable bio bay on the island. While it's not necessary to make a reservation—plenty of operators try to rustle up customers on the docks around sunset—Paradise Scuba runs the most reputable excursions in the area. Visit their dive shop for more information.

The eastern section of the Bosque Estatal de Boquerón is made up of miles of mangrove forests that grow at the water's edge. Boats from the dock in La Parguera can take you on cruises through this important breeding ground for seabirds. You can also organize a kayak trip.

For about $5 per person, boats will ferry you to and from this small island just off the coast for a day of swimming and snorkeling. This island is unique for its fenced in ocean section, providing a safe area for families to swim surrounded by a pier. There are changing rooms and grilling areas. Amenities: showers; toilets. Best for: snorkeling; swimming.

The small beach doesn't compare to some of the longer beaches on the southwestern coast, but it's a convenient place for a quick swim. There's also a square dock built like a picture frame where locals gather to splash in the center of this natural swimming pool.