South. Trains exit the tunnel on the east side of the hill, turning southeast and approaching the elevated Mount Baker station at the intersection of Rainier Avenue South and Martin Luther King Jr. Way South. Light rail trains descend from Mount Baker station onto the median of Martin Luther King Jr. Way South, running at-grade with signal priority at 28 street crossings. The 1Line passes through the Rainier Valley and serves three at-grade stations, , , and , before leaving Seattle. The line enters Tukwila and crosses west over Interstate 5 and a mainline railroad at Boeing Access Road, near Boeing Field, before making a southward turn over East Marginal Way South. The 1Line continues south over the Duwamish River, traveling non-stop through Tukwila on a elevated guideway. The guideway runs along the west sides of State Route 599 and Interstate 5 towards Southcenter Mall, where it turns west along State Route 518. The line passes through Tukwila International Boulevard station, home to a 600-stall park and ride facility, and turns south into the median of the Airport Expressway towards SeaTac. Light rail trains continue along the east side of Seattle–Tacoma International Airport, stopping at SeaTac/Airport station near the airport's terminals, before reaching Angle Lake station, where it terminates. The 1Line, while officially a "light rail" line, has also been described as a "light metro" hybrid by transit experts due to its grade separated sections and use of longer trainsets than typical American light rail systems. Approximately of the line is at-grade, including segments along freeways that are separated from intersecting roads. Stations Stations on the 1Line are spaced approximately apart in most areas and are built with platforms to accommodate four-car train sets. Some stations are grade separated, with underground or elevated platforms connected to surface entrances by stairs, escalators, and elevators, while others were built at street level. The line's sixteen stations include bus connections, ticket vending machines, real-time arrivals information signs, public art, and bicycle parking. Stations are also designed with clear sight lines on platforms, emergency phones and lights, and are monitored with surveillance cameras. All stations are connected to local bus routes, including parallel King County Metro services that stop at multiple Link stations. Since 2019, a set of five stations in the Rainier Valley and Tukwila have had on-demand ride-hail shuttle service that accepts Metro fares and is operated by private contractor Via with