Cairo is an unincorporated community in Malheur County, Oregon, United States. Its elevation is 2192 feet (668 m). It is about four miles (6 km) southwest of Ontario and a half mile north of Cairo Junction, an intersection where U.S. Route 20/U.S. Route 26, running concurrently with Oregon Route 201, turn south towards Nyssa. OR 201 also continues north from Cairo Junction through Cairo and towards Ontario. Cairo was a station on the Oregon Short Line Railroad (OSL) to Vale. The OSL line is now part of the Union Pacific mainline.