Landscape Arch in Utah.

A bit of Rock History: (YABBA-DABBA- Doooooo!)

"Today new arches are being formed and old ones destroyed.
Erosion and weathering work slowly but relentlessly, creating dynamic
landforms that gradually change through TIME.

Change sometimes occurs dramatically. In 1991 a rock slab 60 ft long,
11 ft wide, and four feet thick suddenly fell from the underside of
Landscape Arch, leaving behind an even thinner ribbon of rock.

...In UT's Arches, the minimum (size) consideration for an arch is
three feet. Possibly the longest arch in the world, Landscape Arch measures 306 feet base to base."

April 27, 2009