Possibly stopping there as they traveled between oases and pastures, they ducked into vast subterranean tunnels where molten lava had once ... in the form of rock art, lithic artefacts, stone ...

When you imagine cave paintings, you might picture the famous ... These carvings are etched directly into the lava rock.

Approximately 700,000 years ago when molten rock erupted from a vent in nearby Hart Prairie, the mile-long Lava River Cave was formed. Today, visitors can explore the cave's cool, dark expanse by ...