Just like snowflakes, each one of these wonders is totally and completely unique. Some are made out of ice, some are made out of rock and some are even man-made. That's why you'll want to put visiting all of these formations on your bucket list ASAP.
Advertisement - Continue Reading Below
1
Marble Caves in Chile
Getty
Thanks to 6,000 years of waves slapping up against the calcium carbonate of this rock formation, the underside has eroded into a series of marble caves, featuring shades of teal, yellow, purple and green.
Advertisement - Continue Reading Below
2
Benagil Sea Cave in Portugal
Getty
Even though this natural cave is only accessible by water, it's worth the trip. It features a natural occurring oculus on top of a secluded beach (similar to this one) and is a mesmerizing sight to see when the sun illuminates it from above.
Advertisement - Continue Reading Below
3
Reed Flute Cave in China
Getty
Visitors from all over the world flock to this natural wonder, which was named after the reeds that grow at the entrance to the cave. Colorful lights turn it into an exciting art show.
Advertisement - Continue Reading Below
4
Crystal Caves in Iceland
Getty
These beauties are made out of ice in Icelandic glaciers and glisten even brighter than your prized jewelry collection. But they're only safe to enter during the winter when the temperatures are cold enough to harden the ice.
Advertisement - Continue Reading Below
5
Frasassi Caves in Italy
Getty
Even though these caves were only discovered in 1971, they've easily become some of Italy's most famous underground wonders. Mostly, because they are filled with an abundance of stalactites and stalagmites.
Advertisement - Continue Reading Below
6
Fingal's Cave in Scotland
Getty
Named after the naturalist who discovered this formation back in 1772, this cave is famous for its hexagonally jointed basalt columns, naturally arched roof and eerie sounds made by the lapping of waves.
Advertisement - Continue Reading Below
7
Pak Ou Caves in Laos
Getty
In the Tham Ting, which is the lower cave, there are thousands of Buddha statues covering the limestone cliff shelves. All of the figurines are unique and are in different positions, including teaching and meditating poses.
Advertisement - Continue Reading Below
8
Caverns of Sonora in Texas
Getty
This National Natural Landmark is famous for being filled with an array of calcite crystal formations, especially helictites, which is essentially a twisted or curved stalactite.
Advertisement - Continue Reading Below
9
Spruce Tree House in Colorado
Getty
Mesa Verde National Park features homes built into the side of caves by Anasazi or Ancestral Puebloans back in the 13th century. Amazingly enough, after 700 years paintings of animals are still visible.
Advertisement - Continue Reading Below
10
Glowworm Caves in New Zealand
Getty
It might be hard to see, but the ceiling of these caves are covered in bioluminescent glowworms that give off a blue light. Once visitors' eyes adjust to the dark environment, they'll see what look like a night sky filled with tiny turquoise stars.
Advertisement - Continue Reading Below
11
Deer Cave in Borneo
Getty
As part of the Mulu Caves system, this particular cavern is 570-feet-wide and 400-feet-high. But its real claim to fame is that it features a rock that resembles Abraham Lincoln's profile. We can't make this stuff up.
Advertisement - Continue Reading Below
12
Mammoth Cave in Kentucky
Getty
Not only is this the longest cave system in the world, boasting more than 400 miles of network, but new caves are being discovered continuously. Hence how this subterranean area got its nickname.
Advertisement - Continue Reading Below
13
Kungur Caves in Russia
Getty
This two-mile-long cave system in the Ural mountains is one of the country's oldest and biggest underground wonders. Thousands of tourists visit it each year to see the natural ice formations hidden inside.
Advertisement - Continue Reading Below
14
Cenote Dos Ojos in Mexico
Getty
As part of the third largest underwater cave system, divers from all over the world travel to experience this wonder. And the turquoise water that surrounds it only makes it more magical.
Advertisement - Continue Reading Below
15
Son Doong Cave in Vietnam
Getty
Even though this is the world's largest cave, it was just discovered in 1991. It was created two to five million years ago and is the result of river water eroding away the limestone underneath the mountain, and after time, the weak ceiling collapsing.
Advertisement - Continue Reading Below
16
Predjama Castle in Slovenia
Getty
If you prefer to visit man-made tourist attractions on vacation, you'll love this Gothic castle, which was built directly into the natural rock arch of this cave. However, both are insanely old, with the first historic mention of the castle happening in 1274.
Advertisement - Continue Reading Below
17
Majlis al Jinn in Oman
Getty
Not only is this the second largest cave chamber, but the only way to enter is by being lowered on a special rope. Needless to say, this is a thrill seeker's dream come true. The entrance also provides light during the day.
Advertisement - Continue Reading Below
18
Ajanta Caves in India
Getty
All the way back in the 2nd century BCE, Buddhist monuments were carved into stone and still exist today. A British officer rediscovered them back in 1819, which is why visitors can enjoy the detailed carvings today.
Advertisement - Continue Reading Below
19
Chinhoyi Caves in Zimbabwe
Getty
This series of limestone and dolomite caves has been a popular attraction for divers since 1881. Even though the deepest recorded dive is around 393 feet, no one has reached the bottom yet, meaning there's still more to learn about this unique creation.
Advertisement - Continue Reading Below
20
Ice Caves in Antarctica
Getty
Since Mount Erebus is the warmest place in Antarctica, the combination of heat and ice results in these beautiful ice caves. Inside, many of them feature stunning ice crystal formations.