Velebit
There are hundreds of "holes" on Velebit. It has the largest and deepest caves in Croatia. The three-part "Lukina jama" cave is 1392 m deep, making it one of the deepest caves in the world, and the deepest in southeast Europe, while the "Slovačka jama" is 1320 m. What makes it unique is that it is completely vertical, steepest in the world. At the bottom of the pothole is a water course or siphon with branches that are still unexplored. A kind of leech was discovered in the pothole, which has been ascertained to represent a new species, genus and family; it has been named "Erpobdella mestrovi".
Sima Pumacocha
Sima Pumacocha (possibly from Spanish "sima" deep and dark cavern/abyss, Quechua "puma" cougar, puma, "qucha" lake) is a limestone cave located in the Lima Region, Yauyos Province, Laraos District, in central Peru near the village of Laraos, high in the Andes mountains. At 638 meters deep, it held the record for deepest known cave in South America from 2001 to 2006 when it was surpassed by Abismo Guy Collet. With the entrance being 4372 meters above sea level and the depth being over 500 meters, it is the highest major cave in the world. and It is located at .