Serving as a gateway into the past and an example of the way our planet has evolved, caves have always sparked human interest. While some are inaccessible to tourists, many of the world’s most famous caves contain distinct rock formations, underground bodies of water and other fascinating highlights, making them major attractions for locals and visitors alike.
It’s humbling to think that there are some caves large enough to house skyscrapers and entire New York City blocks within them. Check out our ranking of the largest caves in the world below, and keep reading to find out where you can find them.
10 Clearwater Cave System, Malaysia
Situated in Miri, Sarawak, Malaysia, the limestone Clearwater Cave System consists of a series of interconnected caves, rather than just a single one. Clearwater - on its own - has been mapped to just above 30 miles; however, Clearwater Cave System is more than just its longest member. Discovered in the late 1970s, the cave system exists within Gunung Mulu National Park which is a UNESCO World Heritage Site.
In the Clearwater Cave System, you’ll find an underground river, as well as a plethora of unique rock formations. Containing an exceptionally large passage, the Clearwater Cave System is the longest of its kind in Southeast Asia and serves as a major tourist attraction. The amazing thing about caves is that nobody knows their true size. Sure, Clearwater may rank last, but it is still being explored until this very day.
9 Lechuguilla Cave, New Mexico
Lechuguilla Cave is located within Carlsbad Caverns National Park in New Mexico. A limestone and gypsum cave spanning across more than 138 miles, Lechguilla is full of interesting mineral formations that have attracted the interest of geologists around the world and is thought to be the deepest cave in the United States.
While discovered in the 1950s, approximately three decades would pass before Colorado would permit the cave to be explored further. Since the decade of hair metal, explorers have investigated Lechuguilla Cave while marveling at its beauty.
8 Wind Cave, South Dakota
Wind Cave National Park is one of the oldest of its kind in the United States. Another cave that’s classified as a “maze cave” due to its convoluted structure and many underground passages, Wind Cave's density is staggering, even compared to other caves on this list.
Those visiting the cave should also take some time to explore the national park in which it resides. Wind Cave National Park is brimming with picturesque views and serves as a protective habitat for the local wildlife.
7 Shuanghedong Cave Network, China
The Shuanghedong Cave Network is the longest cave in China, situated in Guizhou. Running for more than 150 miles, the network was discovered in 1987 and, according to Largest.org, is a fine example of underground ecosystems. There are at least three rivers in the lower levels of the cave, as well as a number of waterfalls. Within these bodies of water live creatures such as fish and salamanders.
Since its discovery in the late 1980s, various expeditions have been carried out in an attempt to map the passages and discover the cave's secrets.
6 Optymistychna Cave, Ukraine
Earning the crown for the longest gypsum cave, Optymistychna Cave in Ukraine extends for over 161 miles and is divided into 10 different areas. These are based on the various passage structures and gypsum varieties found within.
Optymistychna Cave, located in Korolivka, Ukraine, is widely known as a maze cave, due to the fact that it is extremely elaborate and a little complicated to navigate. But don’t let that put you off! Visitors should be prepared for a lot of mud, especially in the depths of the cave.
5 Sistema Ox Bel Ha, Mexico
Mexico’s Sistema Ox Bel Ha is located within a 30-mile radius of the country’s other largest cave system, Sistema Dos Ojos. Discovered in 1996 and spanning across 167 miles, Ox Bel Ha is thought to have begun forming approximately 18,000 years ago. The name Ox Bel Ha comes from the Yucatec Maya language and translates to “Three Paths of Water” in English.
Since its formation, Ox Bel Ha has become flooded due to the effects of global warming. Today, the system is valued as one of the prominent sources of freshwater in the region.
4 Jewel Cave, South Dakota
As far as aesthetically pleasing caves go, South Dakota’s Jewel Cave is not to be missed. Nestled in the Black Hills National Forest, this gem (pun intended) boasts beautiful scenery below the ground, as well as above. The name Jewel Cave comes from the colorful crystals that can be found adorning the inner corners of the cave.
There are a number of tours you can take to truly experience Jewel Cave in all its splendor, whether you want to trek to the cave system underground or enjoy the trails on the land above ground.
3 Sistema Dos Ojos, Mexico
Located in Tulum, Quintana Roo, Mexico, Sistema Dos Ojos was discovered in 1987 and has hooked the interest of explorers ever since. Running for over 200 miles, this limestone cave is connected to the underwater cave Sistema Sac Atun. According to Largest.org, Sistema Dos Ojos is considered a prime archeological site. Archaeologists have discovered information within this cave system that has led to many discoveries about a number of cultures.
After the channel connecting Sistema Dos Ojos with Sistema Sac Atun was discovered, this cave system became known as the largest underwater cave in existence.
2 Mammoth Cave, Kentucky
It’s unknown how far Mammoth Cave actually extends, but to date, it has been recorded that the underground system stretched at least 365 miles. New caves in the network are constantly being discovered, so there’s no telling just how expansive the system really is.
Humans have been exploring Mammoth Cave for over 4,000 years and, today, it’s still a major tourist attraction in Kentucky. A particularly stunning cave, it hosts a variety of stalactite formations. These were created through water that leaked through the limestone ceiling of the cave over the millennia.
1 Son Doong Cave, Vietnam
With caverns large enough to house a 40-story skyscraper, the recently discovered Son Doong Cave in Vietnam forces visitors to descend 260 feet just to enter its perimeters. Son Doong was discovered in 1991 by a man named Ho Khanh, who was living in the nearby jungle.
The first expedition to the cave was led by the British Cave Research Association in 2009. They found that Son Doong is approximately three million years old. For those wanting to visit, Oxalis Adventures is the only company to run tours into the caves.