One of the principal laying grounds for endangered olive ridley and leatherback turtles, this wildlife refuge (locally called by its shorter name, 'La Flor') is 20km south of San Juan del Sur. It’s easy to visit on a guided tour from San Juan del Sur or from Playa Hermosa Ecolodge in Playa Hermosa.
Turtles lay their eggs here (usually between 9pm and 2am) between July and January, peaking in September and October. Leatherbacks usually arrive solo, but olive ridleys generally come in flotillas or arribadas, when more than 3000 of them pack the beaches at a time. Some people time these arrivals by moon cycles, but no one really knows for sure until the ladies arrive; call the ranger station if you want to be sure.
When there aren’t any turtles around, the park still has an attractive, undeveloped beach, a couple of monkeys on-site and a few short trails; there’s a decent beach break (right and left) at the northern end. It’s off-limits during turtle season.
You can camp at the reserve. The closest hotels are in Playa El Coco.
Buses pass near the entrance of the park on their daily trips from San Juan del Sur to Playa El Ostional (US$1.50, 50 minutes, three daily). Advise the driver of your destination, and after you get off the bus, follow the signs to La Flor (it's a 300m walk).