Portland International Airport (IATA: PDX, ICAO: KPDX, FAA LID: PDX) is a joint civil-military airport and the largest airport in the U.S. state of Oregon, accounting for 90% of passenger travel and more than 95% of air cargo of the state. It is located within Portland's city limits just south of the Columbia River in Multnomah County, six miles by air and twelve miles by highway northeast of downtown Portland.