"Cave Colors" by Storm Crypt via Flickr Creative Commons

Caving is a growing sport. While much of the land masses have already been explored and the earth’s oceans are slowly being unraveled, caving is still in its infancy. New technology is allowing spelunkers to go farther than they ever could before and virgin caves in the most remote corners of the earth are being documented and traversed one by one. The most famous caves, and the ones that stand out on this list, are the deepest and the ones that hold the most artifacts or archeological remains. Most spelunking tours focus on these.

  1. Gunung Mulu National Park, Malaysia Borneo is home of the largest cave system in Southeast Asia, which continues to lure international caving expeditions. More than 186 miles of cave passages have been mapped and explored, including the World’s largest cave chamber, the Sarawak Chamber.
  2. Gouffre Berger, France Under normal conditions Gouffre Berger is one of the favorite caves in the world for spelunkers for its easy accessibility, size, and beauty. Flooding is common and leads safety concerns and deaths every year.
  3. Ape Cave, Washington This lava tube was created by an eruption on Mount St. Helens almost 2,000 years ago. It extends more than 2.5 miles and is the largest continuous known lava tube in the Western Hemisphere.
  4. Actun Tunichil Muknal, Belize ATM is home to the Cave of the Crystal Maiden where you can spelunk beside ancient Mayan pottery and human remains. You’ll get soaking wet here as you must swim right from the entrance.
  5. Hölloch Caverns, Switzerland Hölloch Caverns is the second largest cave system in the world and extends as much as 118 miles in length. There’s a basic touristy, light section, but guided tours and multi-day expeditions in the cave for advanced spelunkers are available as well.
  6. Dan yr Ogof, Wales This ten mile long cave system in south Wales is thought to go as far as 150 miles. It’s a major showcave and considered the greatest natural wonder in Britain, but also a favorite site for European cavers.
  7. Mammoth Caves, Kentucky The largest cave system in the world and a UNESCO biosphere reserve and heritage site has more than 360 miles of mapped tunnels, although only about ten miles are open to tourists.
  8. Echo Caves, South Africa These caves in Mpumalanga extend for more than 25 miles and were used by the locals to hide from approaching tribes. Fewer spelunkers make their way to this limestone complex, so you’ll likely have the place to yourself.
  9. Bohol, Philippines The province of Visayas is home to the village of Bohol, where numerous cave complexes exist, many of them unexplored. More than 1,400 caves have been found on the island are home to WWII hideouts, underground waterways, rare plant and wildlife, and much more.
  10. Sonora Caverns, Texas New crystals are still forming in much of this vast cave complex in Southern Texas. Filled with loads of sparkling mineral formations from coral trees to stalactites.

Click here for Top 10 Caving Vacations in Europe