Explorers in southern Spain have linked two deep caves into one “supercave system” about 16.4 miles long. The connection sits ...

Deep inside a sealed 40-mile cave system, the team films everything — from blinding white crystal ceilings to ancient jaguar ...

Deep beneath the Balkans, a massive sulfur-fed cave hosts 111,000 spiders in one shared web, defying typical spider behavior.

Using only bare hands and natural materials, an underground cave house was built with a private living room carved deep into ...

Climate history recorded in a calcite deposit in a southern Nevada cave indicates that the hot, arid southwestern United ...

Bowling Green hides Kentucky’s only underground boat ride, a serene glide along a subterranean river that flows through cathedral-like chambers. Lost River Cave blends easy access with genuine ...

If there is, or ever has been, life on Mars, the chances are it would exist in caves protected from the severe dust storms, ...

The cavern along the border of Greece and Albania is home to a terrifyingly high number of two species of arachnids that live ...

A ridiculous but instructive thought experiment involving deep time, plate tectonics, erosion and the slow death of the sun ...

Gamma Ray Spectrometer measurements from Mars Odyssey added another hint: Elevated “water-equivalent hydrogen” in the same ...

Deep in the cave recesses, springs feed a stream. But this isn’t fresh mountain water. It’s a sulfidic brew, loaded with ...

Had one hoped to leave a time capsule for today’s Bostonians in the Permian period 250 million years ago, much less the Pliocene epoch four million years ago , they would have been completely, utterly ...