A carpet of beautiful green forest, that was perforated by two enormous and apparently very deep holes (Sima Humboldt and Sima Martel), was discovered by a pilot in 1961. Sima Humboldt has a depth of 314 metres and Sima Martel is 248 metres deep. Sima Menor contains the stalactites of exotic black mineral called litiophorite, mats and coralloids of opal. The vertical walls of both sinkholes have been insurmountable to plants and animals living on the bottom of both wells. Over a long period of time, there has developed a unique, small ecosystem with such species of plants and animals which are found nowhere else on the Earth.
Sima Humboldt and Sima Martel
