Grants Pass is a city in, and the county seat of, Josephine County, Oregon, United States. The city is located on Interstate 5, northwest of Medford. Attractions include the Rogue River, famous for its rafting, and the nearby Oregon Caves National Monument located 30 miles south of the city. Grants Pass is 256 miles south of Portland, the largest city in Oregon. The population was 34,533 at the 2010 census.