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.
Nettlebed Cave
Until April 2010, when the nearby Ellis Basin cave system was found to be deeper, Nettlebed Cave was thought to be the deepest cave system in the southern hemisphere. It drops 889 metres below its upper entrance (Blizzard Pot) to its lower exit (the Pearse River resurgence), and its 24 kilometres of cave passages make it New Zealand's third longest cave.