King County International Airport - Boeing Field — Seattle, United States

King County International Airport, widely known as Boeing Field, carries the code BFI and sits within Seattle, Washington, just 21 feet above sea level along the Duwamish River valley. Two runways support a mix of cargo carriers, general aviation, corporate jets, and aircraft manufacturing traffic tied to Boeing, whose early operations in the area gave the field its common name. The airport sits well within city limits, closer to downtown Seattle than the region's main commercial gateway, Seattle-Tacoma International Airport (SEA), located to the south. BFI handles a significant volume of air cargo moving through the Pacific Northwest, along with flight testing and pilot training activity, even though it carries little scheduled passenger airline service of its own.