Chevé Cave
Chevé Cave ( ; ) is a deep cave located in the Sierra Juárez mountain range in the southern Mexico state of Oaxaca. As of 2003, its deepest point has been measured at deep, making it the second deepest known cavern in the Western Hemisphere and the world’s 12th deepest cave. The cave's deepest known point is nearly one vertical mile and seven horizontal miles from the entrance, ending in a terminal sump. The present limit of exploration in Chevé, at 9.3 kilometers from the nearest entrance, represents one of the most remote locations ever attained inside any cave on Earth. The logistics of reaching this point are enormous: more than two kilometers of rope need to be rigged and three underground camps established. Chevé is the deepest proven freshwater hydrological system in the world. Temperatures in Chevé are moderate, ranging from . It has been most thoroughly explored under the leadership of caver Bill Stone.
Pettyjohn Cave
Pettyjohn Cave (also known as Wilsons Cave, Pettyjohn's Cave, Petty John's Cave, and other similar spellings) is a karst cave located in Walker County, Georgia on the east side Pigeon Mountain in the Appalachian Plateau of Northwest Georgia. It has a surveyed length of 31,490 ft and reaches a depth of 235 ft. The cave is accessible via a path from a gravel parking area on the side of Rocky Lane. Out of the 242 listed, it is 119th longest cave in the United States as declared by the Georgia Speleological Survey.