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Huge boulder falls, blocks entrance to Yellowstone National Park

National Park Service via AP

This photo provided by the National Park Service shows an unidentified man standing by an SUV-sized boulder sitting on Yellowstone National Park's West Entrance road approximately nine miles inside the park's west gate Dec. 29, 2011. The boulder apparently broke loose from a mountainside several hundred feet above the road early Thursday. Park crews have pushed the rock from the road and are assessing the slope for the potential of further slides.

This photo has a certain timeless quality to it.  I imagine it will be hanging on the wall of a Yellowstone lodge or ranger station for years to come.