Take a walk in the dark through Nahuku, known as the Thurston Lava Tube, a 500-year-old lava cave located at an altitude of 3,900 feet on Kilauea Crater in Hawaii Volcanoes National Park. Lava caves like this are formed when a river of lava gradually builds solid walls and a ceiling. When the lava flow stops and the last of it passes downhill, a cave is formed. These caves can be a few feet high and only yards long, or they can stretch for miles with high ceilings. There are several lava tubes you can visit around the island but Nahuku is the most easily accessible and is a fantastic example of a massive lava cave.

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