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.
Picos de Europa
The Picos de Europa contain many of world's deepest caves, including Torca del Cerro (−1589 m), Sima de la Cornisa (−1507 m), Torca los Rebecos (−1255 m) and Pozo del Madejuno (−1252 m). Discovery of new caves and their exploration still continues.