Cottonwood Canyon State Park, established in 2013, is the second largest state park in Oregon, encompassing 8,000 acres on the lower John Day River. The largest is Silver Falls State Park at 9,064 acres. Park headquarters, about a two-hour drive east of Portland, is adjacent to Oregon Route 206 between Wasco and Condon. The river, which here forms the boundary between Sherman County on the west and Gilliam County on the east, meanders for 16 miles through the arid park.