Cave explorers have traversed what’s now the deepest known cave in Australia. On Saturday a group of explorers discovered a 401-metre-deep cave, which they named Delta Variant, in Tasmania’s ...

Just three years ago, a group of Idaho men traveled to an unnamed Western state and in an unnamed range of rugged mountains, hiked up a steep trail. At the top, they unraveled climbing ropes, stepped ...

Fresh orbital images and new geological analysis have revealed eight mysterious caves on Mars that appear unusually well suited to protect traces of life. Together, these caverns, portals and ...