Sima de las cotorras, Natural sinkhole in Ocozocoautla de Espinosa, Mexico.

Sima de las Cotorras is a limestone sinkhole in the El Ocote Biosphere Reserve, 140 metres deep and 160 metres in diameter, with a straight drop of 97 metres. Its elliptical opening has higher north and southwest rims and a lower eastern rim. About 70 metres down, stalactites and stalagmites show among the exposed rock layers, and caves open in the walls. A tropical forest grows on the floor, with trees up to 30 metres tall.

The sinkhole lies in territory of the Zoque people, who called the area Coita, meaning "place of rabbits." In 1985 the Sima de las Cotorras Ecotourism Center was established to give Zoque families an alternative income, protect the environment and discourage migration. The project built an asphalt road, a restaurant and cabins, and added rappelling and guided tours.

The name comes from the Mexican green parakeets that live here most of the year, flying in and out of the sinkhole in circular patterns. The Zoque, who call the area Coita ("place of rabbits"), run the ecotourism center founded in 1985; guides lead walks to cave paintings and the tropical forest at the bottom.

Visiting requires participation in organized tours from the nearby town, as the depth and steep walls demand proper preparation. Wear sturdy shoes and bring sun protection, as conditions vary greatly depending on the season.

The sinkhole was originally called Sima del Copal, after the copal trees (Protium copal) growing around its rim. Inside, a separate tropical forest grows from the bottom, with cedars and mahogany reaching up to 30 metres; these plant species do not occur outside the depression.