A coral reef is made of thin layers of calcium carbonate A coral reef is made of thin layers of calcium carbonate National Ocean Service National Oceanic and Atmospheric Administration U.S. Department of Commerce
Arches is located in northeastern Utah, near the city of Moab. The park is famous for over 2,000 natural stone arches and offers much to the outdoor traveler. There is a 40-mile paved loop tour of the park with numerous trailheads and outlooks.
Definition of arch for Students. 1  1 : a usually curved part of a structure that is over an opening and serves as a support (as for the wall above the opening) 2  2 : something that has a curved shape like an arch the arch of the foot.