Mammoth Cave
ADDED: Depends on how to defines largest; but Mammoth - Flint Ridge Caves system has certainly world's longest knowntotal of surveyed passage length, I believe now >400 miles.
The Sarawak Chamber is the largest known cave chamber in the world. The Sarawak Chamber is a cave that is located underground in the country of Malaysia.
Mammoth Cave is the largest cave system in all of Kentucky.
Hungary
The Mammoth Cave system, located in Kentucky, is the largest cave in the world.
Mammoth Cave Kentucky
Kentucky.
The Son Doong cave is the largest cave in the world. This cave is located in Quang Binh province,Vietnam.
The world's largest cave system is located in the state of Kentucky. The name of the cave system is Mammoth's Cave. The cave system is part of the national parks.
Mammoth cave.
The largest discovered underground labyrinth is the cave network found in Mammoth Cave National Park in Kentucky. While the Carlsbad Caverns can boast the largest single chamber in the US, the labyrinth at Mammoth is the longest ever found in the entire world.
Well it is mostly found in caves but the largest one was found in Chihuahua, Mexico in an underground cave
terraxixos.com . The largest is now underway in Kansas .