Sistema Sac Actun, the world's largest underwater cave system, spans an impressive 215 miles. This subterranean network of tunnels and crystal-clear waterways is a geological masterpiece with ...

Take an otherworldly journey through Hang Son Doong, the world's largest cave located in Vietnam. The cave is more than 500 feet tall, 650 feet wide, and 29,500 feet long. Video courtesy of Ryan ...

Centuries of eruptions on the Big Island have created hidden ... trying to build atop burial caves, says that whenever human remains are found inside a lava tube, they render the entire cave ...

Inside the pool, illuminated by our headlamps ... ve just completed the first push through what is very likely the largest cave passage in the world.

The State of South Dakota has some pretty famous attractions. Mount Rushmore, Crazy Horse Memorial, The Badlands, Black Hills, the list goes on. But one place that doesn't get mentioned nearly enough ...

VAIL, Ariz. — Exciting things are happening at Colossal Cave for the first time in decades. The team there has uncovered a ...

The Extremes crew had trekked for two days through steep valleys covered in lush jungle to reach Hang son Doong cave. Set deep inside Phong Nha-Ke Bang National Park, it is one of dozens of caves ...

Some 1,500 years ago, Curaçao's first settlers, the South American Arawak, lived in and around the Hato Caves – the biggest caves ... only permitted in one area inside the caves, although ...

With hundreds of jerseys, hats and even a model of the Linc made from Legos, Dave Bergner of Bristol may be Bucks County's ...

Discovered in 1999 inside an abandoned mine in Southern Spain, Pulpí Geode is the largest crystal 'cave' of its kind in the world. But what exactly is a geode and how do crystals form inside them?