Top 10 Largest Natural Caves in the World

Sistema Sac Actun, also known as the "White Cave System", is located in Quintana Roo, Mexico. This vast underwater cave system stretches along the Caribbean coast of the Yucatán Peninsula, with cave branches extending north and west of Tulum. Spanning over 347.8 km, it is one of the largest underwater cave systems in the world. Beyond its stunning beauty, this cave network holds significant archaeological importance, providing insights into various ancient cultures.

The cave contains hundreds of archaeological relics, including evidence of the first humans to settle the peninsula, endangered species, and remnants of the ancient Maya civilization.

The cave's water levels extend for over 345 km. Many believe that these water levels have fluctuated over time, and the surrounding waters may have been crucial during periods of severe drought. During the last Ice Age, the water inside the cave rose to 91 meters, flooding the system and leaving behind traces of prehistoric animals. Despite the cave being completely submerged, human remains have been found in some areas of the site.

Located in South Dakota, Jewel Cave was discovered in 1900 by two men who noticed a cool breeze emanating from a small hole in the ground. The cave system here is adorned with unique calcite crystals, which is why it's named Jewel Cave. Stretching over 322 km, this hidden gem is nestled in the Black Hills National Forest, offering stunning underground and surface scenery. The name Jewel Cave comes from the colorful crystals that decorate its inner chambers.

The cave was formed by the circulation of acidic groundwater. One of its most remarkable features is the incredible mineral formations, which over time have taken on the appearance of candles, flowers, and even spider webs, creating a truly surreal environment.

Shuanghedong Cave is one of the longest cave systems in the world. This limestone cave, formed approximately 100 million years ago, is located in Wengquan town, Guizhou Province, in the southwest of China. Discovered in 1987, it stretches over 242 km and serves as a prime example of an underground ecosystem. The cave, rich in gypsum and dolomite, has a carbon dioxide concentration of about 400 ppm and maintains a consistent temperature of around 13°C.

At least three rivers flow through the lower levels of the cave, along with several waterfalls. Some of these rivers are home to giant cave fish and shrimp. In addition, a variety of creatures such as toads, frogs, salamanders, insects, spiders, bats, leeches, and even fungi have been discovered here. Since its discovery in the late 1980s, more than 20 expeditions, primarily by French and Japanese explorers, have faced significant challenges due to the cave's geography and political circumstances.

Revered as the longest and most intricate cave system in the world, Wind Cave (also known as the Cave of Winds) was the first cave to be designated as a national park due to its exceptional complexity. It became a national park in 1903.

With its labyrinthine design and stunning subterranean passageways, Wind Cave ranks among the largest cave systems worldwide. Extending over 241 km, it is not only visually stunning but also serves as a protected habitat for native wildlife.

Wind Cave is particularly notable for housing 95% of the world's calcite formations, which have developed through the gradual erosion of the cave environment. The cave features a variety of calcite structures, including spires that protrude like swords from the walls and ceilings, forming a “boxwork” pattern. This dense, honeycomb-like network of formations remains one of the cave's most captivating mysteries.

Lechuguilla Cave is located in Carlsbad Caverns National Park in New Mexico, USA. This limestone cave stretches 222.6 km and is the deepest cave in the continental United States, reaching a depth of 489 meters. What makes Lechuguilla famous is its unique geology, rare formations, and pristine condition. The cave's entrance is adorned with striking yellow-tinted sulfur and gypsum formations. Lechuguilla contains a wealth of rare mineral deposits that surpass those of any other cave in the Carlsbad Caverns National Park.

The cave is filled with fascinating layers of minerals, drawing the attention of geologists worldwide. Covered in layers of yellow sulfur and gypsum deposits, it is home to a variety of speleothems (mineral formations created by dissolved minerals precipitating in the cave), many of which are extremely rare. Some of these formations have never been observed anywhere else in the world.

The cave is also thought to harbor rare chemical bacteria that consume minerals like sulfur, iron, and manganese. These bacteria may contribute to the cave’s expansion and shape the unusual speleothems found inside. Other research suggests that some of these bacteria may even have potential benefits for human health.

Vatnajokull Ice Cave is located on the island of Oaefajokull in Iceland. This ancient ice cave has been formed over thousands of years and is situated beneath the highest volcano in Iceland. The Vatnajokull Ice Cave is created by Europe's largest glacier and covers an area of 8,200 square meters, with a maximum depth of 1,000 meters and an average ice thickness of 400 meters.

The most striking feature of this cave is its vivid blue color, which results from the immense pressure exerted by centuries of snow accumulation. This pressure forces air out, leaving behind stunning blue reflections that define the cave’s appearance. It is here that the pure and transparent ice is born.

In the summer, the warm temperatures and sunlight melt the surface of the glacier, and meltwater flows through cracks and crevices, creating smooth, ethereal streams. During winter, the ice cave remains relatively stable, but changes slightly as colder temperatures cause the ice to contract, while warmer weather causes the surface layers to melt. With each season, old ice passages may disappear while new ones form, making the cave a constantly changing spectacle.

Hölloch Cave is located in the Muotathal region of Switzerland, a vast underground wonder that retains much of its pristine beauty. The name "Hölloch" translates to "Hellhole" in English, though the original pronunciation in the local Swiss German dialect refers to something more akin to "slippery." Spanning about 200 km in length and reaching depths of approximately 900 meters, Hölloch is a true natural treasure. Discovered in 1875, this massive cave system is one of the largest in the world and has become a popular tourist destination.

When explorers first ventured into Hölloch in 1875, they uncovered a thick layer of clay nearly 20 meters deep. Today, it stands as Switzerland's largest cave and Europe's second-longest. Notably, it was the first cave system in the world to be fully explored, with over 100 km of passages mapped.

Now, it serves as an exciting adventure for tourists, some of whom may need to crouch or bend over to pass through the narrowest parts of the cave.

Sơn Đoòng Cave is located in the heart of Phong Nha - Kẻ Bàng National Park in Quảng Bình province, Vietnam. It is the largest natural cave in the world, as well as the largest Karst cave globally, with a total volume of 35.8 million cubic meters, a length of 8.573 km, a height reaching 195 meters, and a width up to 150 meters. Not only is Sơn Đoòng the biggest cave, but it also boasts the most stunning stalactites and the longest underground river.

Sơn Đoòng was formed approximately 2-5 million years ago when water from the river flowed through limestone areas that had been buried along fault lines. The water eroded the rock, creating a gigantic tunnel deep beneath the mountains. In areas where the rock was softer, the ceiling collapsed, forming large cave chambers. These collapsed sections eventually became the cave's impressive vaulted ceilings.

The cave was first discovered by a local man named Hồ Khanh in 1990-1991. Seeking shelter from a storm, he stumbled upon the cave entrance but was too afraid to enter. In 2007, a Royal British Expedition conducted a search for caves in Phong Nha - Kẻ Bàng but found nothing. It was after observing the surrounding natural phenomena that Howard Limbert, a member of the expedition, suggested that a large cave had to be nearby. In 2008, Hồ Khanh returned to the forest and finally found Sơn Đoòng. In 2009, he led Howard Limbert and his team back to the cave, which was subsequently named Sơn Đoòng.

Sơn Đoòng offers a unique adventure that few caves can match, with several key features that make it truly special:

• The Vietnam Wall (a 90-meter high stalagmite wall)
• Campsites within the cave
• Dog’s Foot – a natural stalagmite formation
• The Sơn Đoòng Sinkhole

In 2009, Sơn Đoòng was officially recognized by National Geographic and explorers as the world’s largest natural limestone cave. In 2013, it was acknowledged by the Guinness World Records as the largest cave in the world.

While Vietnam is home to the world’s largest cave, Sơn Đoòng, the Miao Room Cave in China ranks as the second largest cave in the world. Located in the mountainous region of Ziyun County in southern China, this cave boasts a volume of 10.7 million cubic meters. It can only be accessed via its underground river. The cave spans an area of 117,986 square meters, large enough to fit four replicas of the Great Pyramid of Giza, equivalent to the size of 22 football fields. Scientists estimate the cave’s length to be about 852 meters, with enough space to house a Boeing 747 aircraft.

Exploring Miao Room Cave feels like stepping into an endless journey. The cave is adorned with numerous stalagmites, some reaching up to 45 meters in height, resembling otherworldly structures. These formations were created over 600 million years ago when the cave was submerged under seawater, accumulating thick layers of sediment over time. During the rainy season, a stream flows through the central gorge, deepening the cave and simultaneously transporting fallen rocks within.

While much of the cave has been mapped using 3D laser technology, it remains largely unexplored. Some sections of the cave are still hidden, marked as black areas on the cave’s map.

Mammoth Cave National Park is located in the heart of Kentucky, USA, and is renowned as the longest cave system in the world, stretching approximately 651 kilometers. Its natural beauty and vast expanse are captivating. The park’s official Facebook page once proclaimed: "The discoveries within Mammoth Cave truly have no end!" Established as a national park on July 1, 1941, Mammoth Cave was designated a UNESCO World Heritage Site on October 27, 1981, and became a biosphere reserve on September 26, 1990.

The history of human presence in Mammoth Cave dates back over six millennia. Numerous Native American skeletal remains have been uncovered in the cave and other nearby caverns during the 19th and 20th centuries.

Mammoth Cave National Park is one of 13 natural landmarks in the USA recognized by the United Nations as a World Heritage Site. Home to around 130 species of wildlife, the park draws more than 2 million visitors annually.