Drift to sleep pondering the waves crashing onto the black-sand beach at Madre Sal, an ecotourism project 25km south of Puerto Arista. Named for a mangrove species, its restaurant (meals from M$100) and thatched two-bed en suite cabañas sit astride a skinny bar of pristine land between a lagoon and the Pacific that’s reached via lancha (M$25) through mangroves.
Guests use candles after the 11pm power shutoff, and crabs skitter along the sand when stars fill the night sky. In season, sea turtles come ashore to lay eggs, and the night watchman can wake you if you want to watch or help collect the eggs for the Boca del Cielo hatchery.
Though the water can be rough, the beach is spotless, and there’s excellent bird-watching in the mangroves, including 13 species of heron. Three-hour lancha trips are available (M$750 per boat, maximum 12 people), including one for bird- and crocodile-spotting.
From Tonalá, take a taxi (M$70 shared, M$300 private) or combi (M$45) to Manuel Ávila Camacho; combis charge an extra M$5 to the embarcadero, or you can walk five minutes or ride on the back of a motorbike (M$10).