Riberas de la Costa Azul, usually shortened to just Costa Azul (or Playa Azul), is a long wide expanse of glittering grey-black sand, interrupted here and there by fishing boats secured by long mooring ropes and waterlogged tree trunks half-buried in the sand. An hour further from Tuxtla Gutiérrez  than Puerto Arista , Costa Azul sees only a fraction of the tourist and weekend-warrior traffic that Puerto Arista, and is more friendly and serene than Boca del Cielo .
The beach at Costa Azul is one of Chiapas ’s best—broad and flat, backed by high palm trees and a smattering of tidy wooden structures. The beach is rarely crowded, and those who do come tend to be locals from Pijijiapán  looking for a relaxing afternoon. Even fewer people stay the night—camping is the only option—so evenings are especially peaceful.
And while the surf remains very strong, most waves break well offshore, making it safer to swim and wade here than many other parts of the Pacific coast. (However, the dark sand can be shockingly hot—take your flip-flops with you if you go walking down the beach!)
An isolated outpost of the state sea turtle protection program, Campamento Tortuguero Costa Azul (no phone) is located on the beach about three kilometers (1.8 miles) west of Costa Azul’s main cluster of palapas. Like its sister installations in Puerto Arista  and Boca del Cielo , Campamento Tortuguero Costa Azul conducts nighttime beach patrols and releases hatchlings into the sea.
Visitors are welcome to join, but rarely do since the activities take place at night and there are no beach accommodations here. It’s a pleasant enough walk during the daytime (or a US$15 boat ride from the embarcadero) and you might be able to see a tank of tortuguitas, recently hatched and awaiting release.
A short distance off the road to Costa Azul, near where it hits the highway, are three large granite rocks bearing ancient carvings. Officially called La Retumbadora, they are more commonly referred to as Los Soldados (The Soldiers), as the largest and best preserved of the group depicts three men wearing what appear to be protective uniforms and headdresses.
Archaeologists believe the stones date to 1200–900 B.C. and were carved by Olmecs, Mesoamerica’s first major civilization and predecessors of the Maya. Ask at the top of the Costa Azul road for directions, as there are no signs.