Abismo Guy Collet
The Abismo Guy Collet (SP-090) is the deepest cave in South America, and the deepest in the world that is formed in quartzite. Located in a tepui in northern Brazil near the border with Venezuela, this cave was first explored by cavers in 2006 to a depth of 671 meters.
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.