Velebit caves
The "Lukina jama" cave is 1431 m deep (2013), the deepest cave in Croatia, 14th deepest cave in the world and the deepest cave in southeast Europe. At its foot, there are ponds and streams including one of the largest known colonies of subterranean leeches ("Erpobdella mestrovi"), which has been ascertained to represent a new species, genus and also family. Other species discovered in the system, include the air-breathing land snails "Zospeum tholussum". Like Lukina jama, Slovacka jama, Velebita and Meduza are also located at the "Hajdučki i Rožanski kukovi" special reserve, a dedicated part of the Sjeverni Velebit national park.
Tham Phra Wang Daeng
Tham Phra Wang Daeng, also known as the Cave of the Monk (), is a deep cave located in Thung Salaeng Luang National Park, Amphoe Noen Maprang, Phitsanulok Province, upper central Thailand. It is the longest cave in Thailand, the distance is about 13 kilometers. Buddhist statues and relics, carvings and reliefs, a subterranean river, multiple bat colonies, and a trove of speleothems populate the cave. In 2003, a biological expedition to the cave resulted in the discovery of new fish species, including discoveries in the Balitoridae and Cyprinidae families.