Photo: Mammoth Cave.
Sistema Sac Actun (Mexico) - 347.8 km
Photo: Feel The Planet.
Sistema Sac Actun is located in Mexico's Quintana Roo state, which is the largest underwater cave in the world. This cave is blessed with natural beauty that makes any visitor admiring. In addition, this cave system is also an archaeological site that helps scientists decipher a number of different cultures.
Jewel (USA) - 289.7 km
Photo: Travel South Dakota.
Jewel Cave was discovered by two men in 1900. The name Jewel has the meaning of gem jewel because in the cave is filled with unique calcite crystals arranged in the very impressive surface of the cave. Jewel Cave is located in the state of South Dakota and is now an interesting discovery destination.
Sistema Ox Bel Ha (Mexico) - 257.1 km
Photo: Alux Diver.
The name Sistema Ox Bel Ha means three underwater paths, this cave is one of the most important sources of fresh water in the state of Quintana Roo. In the summer, many visitors visit Sistema Ox Bel Ha because this is the right time to explore different areas of the cave and enjoy diving.
Optymistychna (Ukraine) - 235.9 km
Photo: Optymistychna.
This magnificent cave of Ukraine was discovered in 1996 and began to open to visitors and to explore since 2010. Optymistychna is a magnificent giant labyrinth and preserved in a "primitive" state. Best.
Wind (USA) - 229.7 km
Photo: Black Hills & Badlands Tourism Association.
"Wind Cave" is located in South Dakota state discovered in 1881 with the most complex structure in the world. The cave has a rare honeycomb boxwork geological form.
Lechuguilla (USA) - 222.6 km
This is a limestone and gypsum cave located in the state of New Mexico, with a strange and rare beauty. In the cave there are ancient fossils such as fossils of corals, sponges, sea algae, arthropods . dating back hundreds of millions of years to help the world's scientific research.
Gua Air Jernih or Clearwater (Malaysia) - 215.3 km
Photo: Philippe Crochet.
Gua Air Jernih cave system in Sarawak, belongs to Malaysia's Gunung Mulu National Park, a UNESCO World Heritage Site in 2000. This cave system possesses an underground river and beautiful rock structure, here is one of the best examples of a cave with a tropical underground river.
Fisher Ridge (USA) - 200.5 km
Photo: Sean Lewis.
Fisher Ridge is a complex cave system in the state of Kentucky, discovered in 1981. Here, researchers have found many unique vestiges related to ancient people.
Holloch (Switzerland) - 200.4 km
Photo: Stoos-Muotatal.
Holloch is located in the Muotathal region of Switzerland, the largest and most extensive cave system in the world as a precious natural treasure. This cave was discovered in 1875, and today has become an interesting tourist destination. In the cave there are very narrow positions, to go through visitors forced to bend down or "bend" people.