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U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC 20590
202-366-4000
A woman looks closely at the lava rock walls of Skull Cave in Lava Beds National Monument. The height of this segment of Skull Cave is a result of three lava tubes having collapsed into one huge cave. This cave contains year-round ice deposits within its depths.
© August 2011 A. E. Crane.
