Rainbow Rock (Arch Rock)

Rainbow Rock, also called Arch Rock, is a natural sandstone formation in the desert of AlUla in north-western Saudi Arabia. It takes the form of a broad stone arch rising above the sand. Its curve recalls the shape of a rainbow, which is the origin of its popular name.

The arch was produced by the erosion that has affected the rocks of the area over very long periods. Sand-laden wind and water wore away the weaker parts of the rock mass until an opening appeared. Such features are common around AlUla, where the same processes created other well-known shapes such as Elephant Rock.

The arch stands in open desert away from built-up areas. Visitors usually reach it in vehicles suited to sandy tracks, and it is often one stop on tours that include other rock formations. Photographers come in the early morning and at sunset, when the colours of the stone become warmer, and at night to photograph the sky through the opening. The site is one of the natural landmarks that present the geology of AlUla alongside the archaeological remains for which the area is better known.