Not really an arch, but pretty cool anyway. This arch was formed when a giant block of sandstone broke away and slide down the side of Paria Canyon. The block of sandstone is huge, it must have registered on the Richter scale when it came down. It moved just far enough away from the side of the canyon to allow the river to flow under it. Now the river is wearing away the lower part and widening the space between the canyon wall and the block.