TriMet, more formally known as the Tri-County Metropolitan Transportation District of Oregon, is a public agency that operates mass transit in a region that spans most of the Portland metropolitan area in the U.S. state of Oregon. Created in 1969 by the Oregon legislature, the district replaced five private bus companies that operated in the three counties; Multnomah, Washington, and Clackamas. TriMet started operating a light rail system named MAX in 1986, which has since been expanded to 5 lines that now cover , as well as a commuter rail line in 2009. It also provides the operators and maintenance personnel for the City of Portland-owned Portland Streetcar system.

TriMet, more formally known as the Tri-County Metropolitan Transportation District of Oregon, is a public agency that operates mass transit in a region that spans most of the Portland metropolitan area in the U.S. state of Oregon. Created in 1969 by the Oregon legislature, the district replaced five private bus companies that operated in the three counties; Multnomah, Washington, and Clackamas. TriMet started operating a light rail system named MAX in 1986, which has since been expanded to 5 lines that now cover , as well as a commuter rail line in 2009. It also provides the operators and maintenance personnel for the City of Portland-owned Portland Streetcar system.