The rivers of hot lava rushing out of an erupting volcano sometimes cool down in an odd way. The outer crust cools down and hardens while molten lava is still emptying out, leaving behind a large hollow tube of volcanic rock which ultimately becomes a tourist attraction. This is the Thurston Lava Tube (Nahuku) at Volcanoes National Park in Hawaii. The short trail through the rainforest is lovely, and an important part of this attraction. The lava tube itself is faintly disgusting, resembling a large intestine. It’s wet and slimy inside due to water constantly seeping through the porous volcanic rock. Not that it’s not interesting, but you wouldn’t want to spend a lot of time in there.
Culture and experiences
Thurston Lava Tube
Interesting, but not a cave you would want to linger in