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 on the moon ...

Bend, Oregon, is not only a haven for outdoor enthusiasts but also a gateway to a fascinating underground world. Hidden beneath its stunning landscapes lie lava tubes waiting to be explored. These ...

A Canary Islands volcano pushed rivers of molten lava through the earth. Now scientists and explorers trek through the cooling underground, looking for insights into life on this planet—and perhaps on ...

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.

Ancient humans left behind numerous archaeological traces in the cavern, and scientists say there may be thousands more like it on the Arabian Peninsula to study. By Robin George Andrews When ancient ...