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.
Lazareva Pećina
The Lazareva Pećina, which translates Lazar's Cave, is the longest explored cave in Serbia. Located in Bor municipality, near Zlot, the cave is also sometimes referred to as Zlotska Cave. According to 2012's "Recent Landform Evolution: The Carpatho-Balkan-Dinaric Region", the cave is long. The cave is situated near the entrance of the deep canyon carved into the mountains by the river Zlotska.