Arches National Park This area is changing and here is why. The story of Arches begins roughly 65 million years ago. At that time, the area was a dry seabed spreading from horizon to horizon. The striking red rock features we see today would have been buried thousands of feet below you, raw material as yet uncarved. Then the landscape slowly began to change due to erosion (National Park Service). The national park lies on top of an underground evaporite layer or salt bed, which is the main cause of the formation of the arches, spires, balanced rocks, sandstone fins, and eroded monoliths in the area. ... Over 5,000 feet of younger sediments were deposited and have been mostly eroded away (Wikipedia). Water shapes this environment more than
