Book an outstanding tour to the Sumidero Canyon and watch it from above. The river carved the land for millenniums and nowadays it’s about 1,000 meters (0.6 mi) from the highest part. On your way up, you’ll stop at four viewpoints to take some pictures and in the last one you can buy some souvenirs.
Then, you’ll head to the pier near Chiapa de Corzo to board a boat. On your way through the Grijalva River you can see the rock formations, some crocodiles, monkeys or even cascades. Once back, you’ll have a city tour in Chiapa de Corzo, a very old town where you can visit a viewpoint, the former church now abandoned, and have some time for shopping before going back to Tuxtla Gutiérrez.