When you take a look at the world on a map, it seems there isn’t much left to discover. There are, of course, the depths of the ocean that are still largely unexplored and perhaps some parts of the poles haven’t yet been seen by human eyes, but other than that it seems that we’ve found almost everything else—until you consider the caves.

These structures are incredible feats of nature and man and many of them are still being discovered today. No one found the Cave of Crystals until 2000 and no one has been able to explore the whole interior due to its extreme heat and humidity. Better yet, the largest cave system in the entire world was just discovered in 2009—and there could be an even larger cave out there, no one knows for sure. These incredible earthly features are being unveiled and explored all the time.

Though you may not be able to visit and get inside some of these caves, they are definitely worth a look. From Patagonia to China, these natural and man-made caves are unbelievable. Check out some of the coolest caves in the world.

1. Marble Caves—Patagonia, Chile

Marble caves Lake General Carrera Chile.

Marble caves Lake General Carrera also known as lake Buenos Aires Chile. Cuevas de marmol lago General Carrera también conocido como lago Buenos Aires Chile. (iStock)

Out in in the turquoise waters of General Carrera Lake sits 5,000 million tons of marble, elegantly shaped by nature into caves. Viewing the caves in person is a far more beautiful experience than looking at any photo, but getting there is more difficult than you can imagine. After a series of flights into the city of Coyhaique, you’ll need to drive another 200 miles and then board a boat, which will get you to the caves.

2. Skaftafell Ice Caves—Vatnajökull National Park, Iceland

Ice cave at Skaftafell, Iceland

Skaftafell, Iceland - 10 December 2012: Man silhouetted standing inside ice cave with textured blue and black ash ice walls gleaming, sand and clear ice floor leading to cave exit at Skaftafell, Iceland (Stock)

Set in the Vatnajökull National Park in southern Iceland, the magnificent ice caves attract travelers from all over. The caves are made of highly pressurized glacier ice and they are an incredible sight. Visit sooner rather than later, who knows when these structures could be gone.

3. Man-Made Caves—Dolomites, Italy

Bells man-made caves

Bells man-made caves in Israel (iStock)

The stunningly beautiful man-made caves that sit high among the Dolomites are the result of a dark, tragic time. The area was the front line between Italy and Austria during World War I and as a result these caves still exist in the mountains and bullet holes still line many of the trees below.

4. Reed Flute Cave—Guangxi, China



The cave that got its name from the type of reed growing outside is a major tourist attraction in the Guangxi province of China. Lit from within by multi-colored lights, being inside the cave is a mind-bending experience—one you shouldn’t miss.

5. Son Doong Cave—Phong Nha-Kẻ Bàng National Park, Vietnam



Initially found by a local man in 1991, the Son Doong Cave in Viestnam was fully discovered in 2009, making it the largest known cave in the world. The name translates to “mountain river cave” and there is, in fact, a quick-moving river within the cave, which is how the cave was initially formed sometime between 2 and 5 million years ago.

Check out more extreme caves around the world.

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