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.
Belum Caves
The Belum Caves is the largest and longest cave system open to the public on the Indian subcontinent, known for its speleothems, such as stalactite and stalagmite formations. The Belum Caves have long passages, galleries, spacious caverns with fresh water and siphons. This cave system was formed over the course of tens of thousands of years by the constant flow of underground water. The cave system reaches its deepest point ( from entrance level) at the point known as "Pataalaganga". In Telugu language, it is called " Belum Guhalu". Belum Caves have a length of , making them the second largest caves on the Indian Subcontinent after the Krem Liat Prah caves in Meghalaya. It is one of the centrally protected Monuments of National Importance.