Hawaii Lava Tubes
October 20, 2004
The photo above showing an underground lava tube (Thurstons Tube) was taken from Kileuea Volcano National Park in Hawaii (big Island of Hawaii), on August 21, 2004. Thurstons Tube is likely the most visited lava tube in the world. Lava tubes are formed when flowing lava cools sufficiently and hardens while still hot lava drains through the developing tube system. Other prominent lava tubes are found in Undara, Oueensland, Australia, Craters-of-the-Moon National Monument in Idaho, Rapa Nui (Easter Island), and Mt. St. Helens National Monument in Washington State.