Located in the states of Puebla and Oaxaca, it covers an area of 490 186 ha.
In the area there is tropical deciduous forest, thorn forest, grassland and xerophilous scrub, oak forest and pine-oak forest. 2,703 species of vascular plants have been recorded and an endemism of more than 30%. The Tehuacán-Cuicatlán valley is considered the center of world biodiversity, given the number of species and existing endemisms, a particular example is constituted by the columnar cacti, such as the roof, the cardonales, the izote, the candelilla, the crown of Christ, the old man, the garambullo, the biznaga, and the elephant foot or pot-bellied palm, an endemic species, as well as some agaves, orchids and oyamel species in danger of extinction.
Likewise, from the geological and paleontological point of view the area is important due to the existence of fossil deposits.
The reservation begins from the city of Tehuacán, using highways no. 131 and 125 and their secondary roads.
