Three Arch Rocks National Wildlife Refuge is a U.S. National Wildlife Refuge off the northern Oregon Coast. It is located on the central coast of Tillamook County, in the northwestern part of Oregon. It is one of six National Wildlife Refuges within the Oregon Coast National Wildlife Refuge Complex and was the first National Wildlife Refuge west of the Mississippi River. In 1970 the Refuge was designated as wilderness. It is one of the smallest wilderness areas in the United States.