On November 12, Arches National Park marks the anniversary of its designation as a national park in 1971. Just north of Moab, Utah, the high-desert park is home to more than 2,000 natural sandstone arches—the densest concentration of arches in the world. Today"s image, North Window, is one of the best-known formations in the park"s Windows Section, where towering fins, openings, and sculpted sandstone create a landscape that looks almost architectural.