High Quality Content by WIKIPEDIA articles! The Applegate River is a 51-mile (82 km) long tributary of the Rogue River in the U.S. state of Oregon. It drains approximately 698 square miles (1,810 km2). Rising in northern California, it soon crosses the border and flows northeast then northwest to meet the Rogue about 6 miles (9.7 km) west of Grants Pass. It drains forested foothills of the Siskiyou Mountains along the Oregon–California border.