FLAGSTAFF — Did you know Flagstaff is home to one of the largest lava tube caves in the country? The Lava River Cave in the Coconino National Forest stretches over a mile underground and was formed ...

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 ...

No trip to Central Oregon would be complete without exploring one of the region's defining geological features: the vast expanses of hardened lava that diverted the Deschutes, formed mounds of gumdrop ...

Add Yahoo as a preferred source to see more of our stories on Google. The Lava River Cave exhaled chilled air. I put on my sweatshirt, despite the hot July day. Though I'd been warned about the sudden ...

Beat the summer heat by going underground. Arizona is home to famous caves, like Kartchner Caverns. Here are 5 of the best ...

I would have never seen them if it hadn’t been for an extremely cold and clear day. The snow-covered Sand Creek Desert, full of buttes and lava flows, seemed to be breathing like a dragon. Through the ...

At a little more than a mile, Lava River Cave is Oregon’s longest intact lava tube. It’s also one of the most popular caves to explore in central Oregon. The cave is part of Bend’s Newberry National ...

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.

While the vast majority of our nation’s natural wonders exist above ground, a select few parks, forests, and national monuments feature a hidden basement level. Mammoth Cave National Park, for example ...

The interior of Lava River Cave, shown here, has intact wall linings that showcase the basalt interior of the lava tubes. While a "flat floor" may be rare inside lava tubes, both on Earth and Mars, ...

A couple in Oregon are selling a house with an added extra room – a large underground lava cave. On Sunday, Suzanne and James Brierley told local news outlet KTVZ 21 they brought the property and ...