Cañón del Sumidero
This is a long canyon, with steep sides up to 1km high. There is a river running the length of it, upon which boat tours are run.
Flora and fauna
An all inclusive tour from San Cristobal de las Casas costs 300 pesos in high season (as of July 2013). If you don't want to go on a tour you can get there yourself by colectivo. MX$50 is the one-way fare from San Cristobal. Ask the driver to drop you opposite the “embarcadero” - look out for the signs about 1km after you pass the junction for Chiapa de Corzo and remind him. Do not get out at the Chiapa de Corzo turnoff itself, or change to a colectivo that takes you into town, you will have wasted time and money.
After getting dropped near the embarcadero cross the highway and walk a couple hundred metres down the small road until you see a parking lot with lots of busses and stalls selling the usual tourist souvenirs.
MX$200 is the official price for the boat ride through el Cañón and is non-negotiable. Make sure you receive a wristband after paying, you will need to show it to a park ranger at a checkpoint downriver. The boatride takes about two hours and the boats are unprotected from the elements, so bring appropriate clothing for the prevailing conditions (and sunscreen if you’re lucky and the sun is shining).
If you're staying in Chiapa de Corzo you can go to the riverside in town, there's a boat tour company offering a 2 hour boat tour for MEX$230 (as of January 2019).
MX$200 for a boatride.
Crocodiles and birds in beautiful nature.
Take lots of pictures.
There are plenty of stalls near the embarcadero selling the usual tourist knick knacks.
There are a couple of restaurants in front of the embarcadero and a small shop selling basic snacks.
If you walk back up the road you walked in on, there is a big blue bus sign you can wait in front of for passing collectivos. They pass very regularly and it is unlikely that you will have to wait for long. As of December 2015, they will charge you 50 pesos to San Cristobal.