Portland International Airport is a joint civil-military airport and the largest airport in the U.S. state of Oregon, accounting for 90 percent of passenger travel and more than 95 percent of air cargo of the state. It is located within Portland's city limits just south of the Columbia River in Multnomah County, 6mi by air and 12mi by highway northeast of Downtown Portland. Portland International Airport is often referred to by its IATA airport code, PDX.Portland International Airport has direct connections to some major airport hubs throughout the United States, and non-stop international flights to Canada, Germany, Iceland, Japan, Mexico, the Netherlands and the United Kingdom. The airport is a secondary hub for Alaska Airlines and Horizon Air, with Seattle–Tacoma International Airport as the primary hub for Alaska Airlines and Horizon Air. The airport also serves as a maintenance facility for Horizon Air. Regional carrier PenAir operate their Pacific Northwest hub at PDX. General aviation services are provided at PDX by Atlantic Aviation. The Oregon Air National Guard has a base located on the southwest portion of the airport property grounds, and is also the host unit of the 142d Fighter Wing (142 FW) and the F-15 Eagle. Local transportation includes the MAX Red Line light rail, which takes passengers between PDX and Downtown Portland, as well as farther west to Beaverton, Oregon. There is also Interstate 205, which connects to southwestern Washington (north from PDX) along with many suburbs of Portland (south from PDX).