A mile and a half beneath the ocean’s surface, the seafloor seems nearly as alien as the surfaces of other planets. Deep-sea volcanic ridges, formed by the collisions of tectonic plates, create ...

The Chauvet-Pont D'Arc cave is one of the most famous underground caverns in the world, housing one of the oldest and best-preserved collections of prehistoric cave paintings ever discovered. Now, ...

A team of Chinese researchers has identified eight caves in Mars’ Hebrus Valles that may have been sculpted by water. These ...

SAN VICENTE PACAYA, Guatemala -- It's the only place in the world where you can hike up a volcano and once done, enjoy an artisanal pizza cooked inside a volcano! Based in Guatemala, Pizza Pacaya was ...

Oregon has no shortage of staggering natural beauty, from prominent icons like Mount Hood to under-the-radar marvels like the secret "Iceland-esque" Abiqua Falls just south of Portland. Yet Oregon's ...

A staircase leads to the entrance of the Lava River Cave at Newberry National Volcanic Monument. (Courtesy Dylan Lipke) When it feels difficult to escape the summer heat, sometimes it helps to head ...

Mountaineers, cavers, and scientists ventured into the inhospitable caves at the giant volcano’s peak to learn more about how this frozen environment is changing over time. Tabby Cavendish, a ranger ...

A mysterious pit on the flank of an ancient volcano on Mars has generated excitement recently because of what it could reveal beneath the surface of the Red Planet. Here's what that means. First ...