6 Best Sights in El Yunque and the Northeast, Puerto Rico

Cayo Icacos is one of about 10 small islands that make up the Cordillera Nature Reserve just off the coast of Puerto Rico. It's a beautiful beach with good snorkeling offshore. Icacos can only be reached by a 15- to 20-minute boat ride, so pack whatever you might need for the day. Several tour operators in Fajardo offer day trips here, or you can hire a boat in Las Croabas. Amenities: none. Best for: snorkeling; solitude; swimming; walking.

The 316-acre reserve on a headland north of Fajardo is owned by the nonprofit Conservation Trust of Puerto Rico. You ride in open-air trolleys and wander down boardwalks through seven ecosystems, including lagoons, mangrove swamps, and dry-forest areas. Green iguanas skitter across paths, and guides identify other endangered species. A half-hour hike down a wooden walkway brings you to the mangrove-lined Laguna Grande, where bioluminescent microorganisms glow at night. The restored Fajardo Lighthouse is the final stop on the tour. Its Spanish colonial tower has been in operation since 1882, making it Puerto Rico's second-oldest lighthouse. The first floor houses ecological displays, and a winding staircase leads to an observation deck. The only way to see the reserve is on a guided tour; reservations are required and can be made through the trust's website.

One of Puerto Rico's prized Blue Flag beaches, this long stretch of powdery sand near the Reserva Natural Las Cabezas de San Juan has calm, clear waters that are perfect for swimming. There are plenty of picnic tables, as well as restaurants just outside the gates. Amenities: food and drink; parking (fee); showers (fee); toilets. Best for: swimming.

A few miles north of Fajardo is this fishing area, where seafood is sold in open-air restaurants along the ocean. A small park in the middle of town has a lovely waterfront walk, and it's easy to find outfitters for any kind of ocean adventure, from kayak excursions to sailing trips.

This lively marina off Route 987 is home to a cadre of glistening fishing boats and the offices of Kayaking Puerto Rico.

Home to 1,000 slips, Puerto del Rey claims to be the Caribbean's largest marina. This is the place to hook up with a scuba-diving group, arrange an excursion to one of the bioluminescent bays, or charter a fishing boat. The marina, located south of Fajardo, also has several restaurants and boating-supply stores.