The mountains behind Chiapa de Corzo , and throughout Chiapas  for that matter, are perforated by countless channels formed by underground rivers. That water eventually reemerges, as at El Chorreadero (literally The Spout). Located about 10 kilometers from Chiapa de Corzo, El Chorreadero (Carretera Libre a San Cristóbal, 8 a.m.–6 p.m. daily, US$1) is a 25-meter waterfall pouring out the mouth of a cave, partway up a soaring stone cliff.
A slippery pathway climbs up into the gruta (cave), where you can walk about 50 meters to the edge of a dark interior lagoon fed by another waterfall. It’s no Victoria Falls, but an interesting sight nonetheless, and a popular local getaway on hot days, with several swimming holes and a small restaurant and bathrooms (albeit pretty grubby).
El Chorreadero is the end of a nearly 3-kilometer underground journey of the Río Escopetzo; there’s a surprisingly good map, with explanations in Spanish and English, near the entrance.
To get there by car from Chiapa de Corzo , take the carretera libre (free highway) toward San Cristóbal  to the well-marked turnoff. Otherwise, combis marked Chorreadero, Bochil, or Ixtapa will drop you at the turnoff (US$1, 15 mins); from there, it’s another kilometer downhill to the entrance.
The combis can be caught in Chiapa de Corzo near the Pemex gas station or the Monumento Chiapaneca y Parachico (statues of two traditional costumed dancers), both several blocks from the central plaza.