On Vancouver Island, karst researchers hustle to save one of Earth’s most underappreciated—and fragile—ecosystems: an ecosystem hidden in plain sight. By Bruce Grierson.

A massive pit that was spotted in a remote high alpine valley in British Columbia’s Wells Gray Provincial Park earlier this year is the entrance to a previously unexplored cave of “national significance,” say two members of a Canadian team that helped conduct a preliminary exploration of the site in September.

New record of ice age climate from Brazilian caves tells of rainy times. By Scott K. Johnson.

Scientists have long been trying to figure out how exactly our ancestors evolved from fish to land vertebrates some 375 million years ago. Now a tiny, eyeless fish that walks and climbs up waterfalls could offer some clues... By Kaitlyn Tiffany.

Georgy Tarasov

A study of the subglacial caves could reveal new undiscovered animal or plant species living comfortably due to the heat of an active volcano. By Victor Ferreira.

The cave, beneath a farmer's field in Shropshire, was used by the medieval religious order that fought in the Crusades and these stunning images were captured by photographer Michael Scott

In a Mexican cave system so beautiful and hot that it is called both Fairyland and hell, scientists have discovered life trapped in crystals that could be 50,000 years old.

Anthropologists in Germany say they may not need old bones to recover ancient DNA. They just analyze dust from the floor of caves where Neanderthals and other now-extinct human relatives once resided. By Joe Palca.

This Colorado cave holds beautiful crystals, blood-red worms, and mysteries for the scientists who have now explored it.

A blind, walking cavefish in Thailand can climb up steep, slippery rocks in rapidly flowing water thanks to a pelvis bone that’s remarkably similar to that of four-legged landlubbers. The findings, published in Scientific Reports this week, could help us understand the transition from finned to limbed appendages that took place some 420 million years ago.

Even when temperatures climb into the high teens, ice caves a few metres below ground remain frozen solid

Slovenia’s karst territory is a breathtaking and bizarre underworld where unimagined creatures swim through lightless grottos and monstrous caverns are used as concert halls.

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With more than 30 years of experience as a cave explorer and guide under his belt, Australian photographer John Spies is an expert at navigating the incredible formations and winding passages of underground sites never before seen by man.

Suspended on a thin rope, engulfed in cloud and lost in time, a tiny figure is dwarfed by the sheer size on a monumental scale of Cloud Ladder Hall in Dong Wan Dong cave. The beam of light cast by another's headtorch pierces the fog yet illuminates nothing. “This naturally formed room is so large it has its own weather system,” says Robbie Stone, the photographer.

Austrian balloon pilot Ivan Trifonov has succeeded in taking a balloon deep underground. The feat, which is believed to be a world first, was filmed and is being submitted to the Guinness Book of World Records.

Sơn Đoòng Cave was found by a local man named Hồ-Khanh in 1991. The whistling sound of wind and roar of fiery stream in the cave heard through the entrance as well as the steep descent prevented the local people to enter the cave. Only in 2009 did the cave become internationally known after a group of scientists from the British Cave Research Association, led by Howard and Deb Limbert, conducted a survey in Phong Nha-Kẻ Bàng from 10 to 14 April, 2009.

Uphill from the giant Miao Room, 21 families from the Miao minority live under the roof of a cave. They first came, elders say, because of the reliable spring. The cave now contains a basketball court and, until recently, had a school.

The sandstone cliffs of Afghanistan's Bamiyan province are most famous for the giant 6th century Buddha statues carved out of the rock and destroyed by the Taliban in 2001. The monks who created them also dug out numerous caves in the Bamiyan valley. Originally used for meditation and retreat, some of these caves are now home to around 700 Afghan families who have no land and can't afford conventional housing.