The Canary Islands not only boast the third largest volcano in the world, but also the largest natural underwater lava tunnel. Mount Teide, the third largest volcano, resides in Tenerife ...

Possibly stopping there as they traveled between oases and pastures, they ducked into vast subterranean tunnels where molten lava had once flowed millions of years earlier, according to a recent ...

Here’s everything you need to know about the Undara Lava Tubes ... a leisurely two-hour Archway Explorer Tour, a more adventurous Wind Tunnel Explorer Tour, and a fascinating Wildlife at ...