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 ...

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 ...

Lava tubes can range in size from a small hollow ... Miller collects a mineral sample from a cave filled with toxic gases. Among the rare minerals found so far is wulffite, recorded only once ...

The Canary Islands not only boast the third largest volcano in the world, but also the largest natural underwater lava tunnel ... and a blend of dry and submerged cave sections.

From within the dungeon, after heading south from the lava-filled room with all the connective ... You'll end up on a long rock balcony with two cave entrances. One is the exit you just came ...

It includes Geomunoreum, regarded as the finest lava tube system of caves anywhere, with its multicoloured carbonate ... multi-shaped rock formations, and lake-filled crater. The site, of outstanding ...