About 15 kilometers (9 miles) down the coast from Puerto Arista , Boca del Cielo is set on a narrow spit of sand separated from the mainland by a shallow inlet. It is far less developed than Puerto Arista, with sand-floor restaurant-posadas, (known as palapas) instead of modern hotels, and a quieter, more laid-back scene.
Still, Boca del Cielo’s proximity to Tuxtla  means it gets crowded on many weekends and holidays, and prices are higher than one might expect.
Boca del Cielo’s main draw is its beach—a broad expanse of grey-black sand that extends for what seems like forever in either direction. Like much of Chiapas ’s coastline, the beach appears desolate at first, but has a sparkling scenic beauty that grows on you. The beach has fewer visitors and less boat traffic than at Puerto Arista, not to mention fewer vendors and less litter.
Although the ocean here can be equally rough, the inlet offers safer swimming and wading, especially for kids. (Just be alert for boats and strong currents, mainly near the mouth of the inlet.)
Campamento Tortuguero Boca del Cielo (no phone, 8 a.m.–5 p.m. daily), another of the four sea turtle protection installations along this coast (others are in Puerto Arista , Costa Azul , and Barra de Zacapulco ), this one’s run by a friendly two-person team. The program does nightly beach patrols in search of fresh nests (around 7–11 p.m.) and frequent hatchling releases (around 5–7 p.m.).
Tourists are welcome to take part in either; drop by during the day to sign up, and the staffers will swing by your palapa that evening. The most active months are July to November for beach patrols, and May to October for hatchling releases.
Boca del Cielo is 15 kilometers east of Puerto Arista ; there’s a well-marked turnoff about two kilometers north of Puerto Arista (and 14 kilometers south from Highway 200). From there it’s 16 kilometers to a second turnoff, which leads a kilometer more to Boca del Cielo’s main embarcadero.
Combis and collective taxis come and go from the embarcadero parking lot (aka el caracol) every 30–60 minutes from 5:30 a.m. to 6 p.m. daily. It’s US$1.25 to the Puerto Arista turnoff (20 mins), and US$1.75 (1 hr) to Tonalá .
Motorboats, or lanchas, shuttle passengers across the narrow lagoon separating the mainland from the beach and oceanfront palapas. The fixed rate is a ridiculous US$7—it’s all of 90 meters—but the return trip is customarily paid for by the palapa where you eat or stay.