The Portland Transit Mall is a public transit corridor that travels north–south through the center of downtown in Portland, Oregon, United States. It comprises a pair of one-way streets—6th Avenue for northbound traffic and 5th Avenue for southbound—along which two of three lanes are restricted to transit buses and light rail vehicles only. , the corridor is served by the Green, Orange, and Yellow lines of MAX Light Rail; Frequent Express; and over a dozen local bus routes, all of which are services of TriMet, the transit agency operating within the Oregon side of the Portland metropolitan area. C-Tran, the transit agency for Clark County, Washington, additionally serves it with two express bus routes—#105 I-5 Express and #164 Fisher’s Landing Express. The transit mall was conceived as part of Portland's 1972 Downtown Plan. It opened in 1977 and until light rail trains were added in 2009, buses were the only transit vehicles using it. The mall was rebuilt and extended southwards from 2007 to 2009, and it reopened for buses on May 24, 2009. Light rail service on the mall was introduced on August 30, 2009, with the shifting of the MAX Yellow Line to the mall from its original routing in downtown, and a second MAX line, the Green Line, began serving the mall two weeks later, on September 12. Between fall 2009 and July 2014, the Portland Vintage Trolley also served the transit mall on certain Sundays. In September 2015, the new MAX Orange Line replaced the Yellow Line service in the southbound direction on the mall, on 5th Avenue, with the Orange and Yellow lines being through-routed at all times. History The Portland Transit Mall (formally named simply the Portland Mall) was constructed by TriMet, the Portland metropolitan area's regional transit agency, in 1976–77 and opened on December 11, 1977. It was formally dedicated in March 1978. The mall comprises 5th Avenue, for southbound buses, and 6th Avenue, for northbound buses, and when first opened it involved the sections of those streets extending from West Burnside Street to SW Madison Street: the central core of downtown. In June 1994, the mall was extended northward through Chinatown to Union Station (used by Amtrak) and the Greyhound bus depot. Short, unconnected additions were made in the area around Portland State University in the early 2000s. TriMet's Fareless Square (renamed the "Free Rail Zone" in 2010) encompassed the entire mall