Las Baulas national marine park encompasses the entire beach at Playa Grande, as well as the adjacent land and 220 sq km of ocean. This is one of the world's most important nesting areas for the critically endangered baula (leatherback turtle). In the evenings from October to March, rangers lead tours to witness the turtles' amazing cycle of life.

　　Despite increased conservation efforts, fewer leatherbacks are nesting on Playa Grande each year. To protect the dwindling population, park rangers collect eggs and incubate them to increase their chances of survival. Even so, sea turtles must hatch on the beach and enter the water by themselves, otherwise memory imprinting does not occur, and the hatchlings will never return to their birthplace to nest. It’s estimated that only 10% of hatchlings survive to adulthood.

　　The park office is by the northern entrance to Playa Grande. Many agencies in Tamarindo book all-inclusive tours.

　　The show kicks off after 9pm. Tourists are not allowed on the beach until the turtles have made it to dry sand. (Be prepared to wait. It's well worth it.) Photography, filming and lights of any kind are prohibited. Over the span of one to two hours, you can watch as each turtle digs its nest, lays about 80 to 90 shiny silver eggs and then buries them in the sand.