Sometimes, a hole in the ground is just a hole. Other times, it’s a portal to an underground cave spanning miles in width and length. You don’t really know what’s inside unless you dive into the void.

Mars skylights like this could be the mouths of caves formed by lava tubes. NASA wants to explore them. Credit: NASA / JPL-Caltech / Univ. of Arizona Ever since scientists have had an orbiter's view ...

It’s tempting to write this like a James Michener novel, going back to the beginning of time to give the history of Kuna Cave. The Idaho Press can’t afford that much paper, so I’ll simply explain how ...

If human beings want to survive on the other planets for a long time, they must first find or set up a safe, stable, and long-term shelter. Lunar lava tubes are geological structures of the moon ...

Volcanic rock in the lava tubes created a protective environment that helped shield the minerals and organic compounds from weathering, ultimately preserving the minerals as records of past ecosystems ...

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

If human beings want to survive on the other planets for a long time, they must first find or set up a safe, stable, and long-term shelter. Lunar lava tubes are geological structures of the moon ...

Another world greets you just a short 30-minute drive from the Icelandic capital Reykjavik. Raufarhólshellir Lava Tunnel is a terrific example of a lava cave created following a volcanic eruption ...

For decades, scientists have theorized the existence of lunar caves - underground tunnels formed by ancient volcanic activity and connected to the moon's numerous pits. Now, a groundbreaking discovery ...