Chiapanecans. The coat of arms of Chiapas appears, as it was a stage for a battle between the Spanish and the
Chiapanecans, which gave origin to the legend that the Indians preferred to
jump to the depths of the canyon, rather than be submitted to their invaders.
The Spanish triumph motivated that Charles V give, to the capital of the
province, the present San Cristobal, the coat of arms, which now belongs to the
state. Travelling through the canyon, requires an attentive observation, since, the
interest is not only in the geological formations, but in the fauna, the flora, and
the archaeology as well. From the geological point of view, it shows a series of
pits, that from their original openings, the water, with the running of time, has
erosioned them. Their original modeling must have began at least 12 million
years ago. Throughout the Sumidero canyon, it is possible to appreciate the
sedimentary layers that constitute its walls, the caves and cascades that have
marked its rocky stratum, derived by the dissolution of the limestone areas.
Most of the cascades are temporary; and amongst these, the best known is the
one called "The Christmas Tree". The vegetation is rich and varies in accord
with the humidity conditions, exposure to the sun, and the type of soil.
Regarding the fauna, birds are abundant, but you can also see species of 
monkeys and crocodiles. At the
canyon’s entrance, hidden amongst the trees, are the ruins of a Chiapanecan
ceremonial center, perhaps dedicated to Mandanda, the goddess of water, and
which was one of the stages of the conquest.There are different versions about the dimensions of the canyon. In the case of longitude, these vary from 13 to 22 kilometers in function of what is considered an initial point and final one. The same happens with its width, that goes from 200 meters from the water level to 2 kilometers, at the highest point. More controversial, is the maximum height, which, according to books varies between 700 and 1400 meters. After the construction of the Manuel Moreno Torres dam, and with the rising of the waters, they now affirm, that the maximum height of the walls doubtfully surpass 800 meters.
It is possible also, to drive through the National park, over a paved highway which parts from Tuxtla Gutierrez, to five different lookouts: La Ceiba, La Coyote, El Roblar, El Tepehuaje, and Los Chiapa, this last one, 22 kilometers from the capital. The view from these highpoints and the rich and changing vegetation, make this a very different experience.