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 ...

With its iconic mountains, rivers, and coastline, it’s easy to overlook the adventure of discovering some of Oregon’s underground wonders. Oregon is home to some of the best examples of deep caves and ...

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.

A large lava tube—a cave formed from a volcanic eruption—was discovered beneath a home in Bend in central Oregon. Back in 2017, realtors told Suzanne and James Brierley that there was a small cave ...

Centuries of eruptions on the Big Island have created hidden networks of passages beneath volcanoes. In December 2016 a large lava delta formed by Kilauea volcano sank into the sea, exposing the mouth ...

My Arizona bucket list is long, and I think scrolling on social media is to blame for that. Researching things to do and places to see, I am always amazed at how much the state has to offer. While my ...