Kaumana Caves, Hilo, Hawaii

The Kaumana Caves are part of a 25-mile-long lava tube located on Hawaii's Big Island. Set on a hilltop above Hilo, the cave's entrance – actually a skylight formed when part of the lava tube collapsed – is open to curious visitors who want to explore the inside. (A lava tube is a natural tunnel formed by flowing lava which moves beneath the hardened surface of a lava flow. Tubes can be actively draining lava from a volcano during an eruption, or can be extinct, meaning the lava flow has ceased and the rock has cooled and left a long cave-like channel.) 

A concrete staircase leads down into the skylight that forms the entrance to the caves. The section of the caves open to the public stretches for approximately 2 miles. Many areas near the entrance are lit by sunlight, but the cave is damp, cool and often muddy, with lots of vines, ferns and roots hanging down from the entranceway and the ceiling. Visitors can observe a wide variety of lava formations, including some rock that is red because it cooled so fast during the 1881 flow that it retained its color.  

The Kaumana lava tube was formed by lava flow from Hawaii's Mauna Loa in 1881. The eruption of the giant volcano actually occurred on Nov. 5, 1880, but the lava continued its slow approach on Hilo through the first few months of 1881. By late June, it was within 5 miles of the town and began picking up speed. Legend has it that Hawaii's Princess Ruth, sent from Honolulu, is responsible for saving the then-tiny village because she was carried into the hills in late July and took up a position in front of the lava, praying to Pele, the Hawaiian goddess of religion and fire, to spare the town. The flow began slowing, and finally stopped in early August, just 1.5 miles from Hilo Bay.  

Dan and I didn't venture too far into the tube, maybe just 1/4 mile in each direction, but far enough to notice that without our flashlights we would be in absolute darkness. For the serious spelunker, long pants, headlamps, and closed toed shoes are recommended to traverse all of the accessible parts of this cave.