King County Metro operates a weekend express shuttle between Seattle and hiking areas in the Cascade foothills called Trailhead Direct from April to October. The service, operated in partnership with the county's park and recreation department and private companies, debuted in 2017 and was expanded the following year to cover three routes: Capitol Hill station to Mount Si; Mount Baker station to the Issaquah Alps; and a shuttle from North Bend to Mailbox Peak. A fourth route, between Tukwila International Boulevard station, Renton, and Cougar Mountain, was added in 2019.