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.
Tears of the Turtle Cave
Tears of the Turtle Cave is located in the Bob Marshall Wilderness in western Montana and is currently the deepest limestone cave in the United States since passing New Mexico's Lechuguilla cave in 2014. As of August 2016 the cave is known to be 1659 feet deep and 1.32 miles long. The cave consists mostly of roughly 2 foot wide fissure passage passing over dozens of short rope drops. With a mean temperature of 39 degrees F (4 C), it is muddy and poorly decorated.