4 Best Sights in Guanacaste and the Nicoya Peninsula, Costa Rica

Encompassing more than 1,000 acres of beach, mangrove swamps, and estuary, and more than 54,000 acres of ocean, this wide expanse of sand and sea will make you feel small, in the best way possible. Baula is the Spanish word for leatherback sea turtles, who have been nesting here for thousands of years. While their numbers continue to decline, guides still lead night hikes here between October and May to see leatherback and olive ridley sea turtles lay their eggs. You can also spot scores of native birds like brown-footed boobies and pelicans, kayak through the mangroves and estuary, or learn to surf on some of the best waves in the country. There are no hotels or restaurants on the beach thanks to government regulation preventing development, but there is a taco stand and a ranger station open from 8 am to 4 pm at the entrance to the beach. Be sure to bring water and sunscreen, and your own shade. The park closes to the public at 6 pm and 5 pm during turtle nesting season.

This wildlife refuge protects one of Costa Rica's major nesting beaches for olive ridley turtles. If you get to go when the turtles are hatching, it is a magical experience. Locals have formed an association to run the reserve on a cooperative basis, and during the first 36 hours of the arribadas (mass nesting) they are allowed to harvest the eggs, on the premise that eggs laid during this time would likely be destroyed by subsequent waves of mother turtles. Though turtles nest here year-round, the largest arribadas, with thousands of turtles nesting over the course of several nights, occur from July to December; smaller arribadas take place between January and May. They usually occur around high tide, the week of a new moon. It's best to go very early in the morning, at sunrise. People in Nosara can tell you when an arribada has begun, or check the Facebook page Asociacion de Guias Locales de Ostional (AGLO) Costa Rica. To avoid overcrowding on the beach, visitors must join a guide-led tour of the nesting and hatching areas for $20 per person. Stop at the kiosk at the entrance to the beach to arrange a tour, or at the Association of Guides office, 25 meters (82 feet) south of the beach entrance on the main road, next to Cabinas Ostional. A new bridge over the Río Montaña has made access easier from Nosara, but it's sometimes difficult to get to from the north during rainy season (May to mid-December).

Sad but true, one of the few places left in the country where you are guaranteed to see large wild cats, including a jaguar, is this animal rescue center. The small enclosures also hold jaguarundis, pumas, margays, and ocelots. The shelter houses other species, including otters, grissons, white-faced and spider monkeys, and scarlet macaws, all native to the area. Some animals and birds are rehabilitated and released into the wild. The larger cats are probably here for life, as it's dangerous for them to be released. Donations to the nonprofit foundation, founded in 2003 by a Swiss conservationist, are welcomed.

Playa Grande used to host the world's largest visitation of nesting giant leatherback turtles, but the number of turtles has fallen drastically in the past 20 years, from a high of 1,504 in 1989 to less than 40 currently. This loss is due to long-line commercial fishing boats that trap turtles in their nets, causing the turtles to drown, along with poaching of turtle eggs and loss of habitat. The beach is still strictly off-limits 6 pm to 6 am from October 20 to February 15, during the peak nesting season. You can visit only as part of a guided tour with a park ranger, from the headquarters for Las Baulas National Marine Park, 100 meters (328 feet) east of Hotel Las Tortugas. If you are lucky, spotters will find a nesting turtle. At their signal, you'll walk down the beach as silently as you can, where in the darkness you'll witness the remarkable sight of a 500-pound creature digging a hole in the sand large enough to deposit up to 100 golf-ball-size eggs. About 60 days later, the sight of hundreds of hatchlings scrambling toward open water in the early morning is equally impressive. Turtle-watching takes place around high tide, which can be shortly after sunset, or in the early morning. Plan on spending one to six hours at the ranger station waiting for a turtle to come up, during which you can watch a video on the turtles in English (the guides speak mostly Spanish). You are charged only if a turtle sighting is confirmed. Visitation is limited to 60 people per night (in groups of 15 max) and unregistered visitors are not allowed. Reservations should be made one week in advance either by phone or at Las Baulas National Park headquarters at Playa Grande.