For nearly fifty miles, from the mouth of the Siuslaw, to Cape Blanco at Coos Bay, the largest area of dunes in the country lies between the Pacific Ocean and the Coast Mountains. In places, the dunes extend 2.5 miles inland, and some are as high as 500 feet. In 1972, 32,186 acres of dunes, forest, streams, and lakes were set aside as the Oregon Dunes National Recreation Area.