The Metro Green Line (formerly called the Central Corridor) is an light rail line that connects the central business districts of Minneapolis and Saint Paul in Minnesota as well as the University of Minnesota. An extension is under construction that will extend the line to the southwest connecting St. Louis Park, Hopkins, Minnetonka and Eden Prairie. The line follows the path of former Metro Transit bus route 16 along University Avenue and Washington Avenue (which runs from downtown Minneapolis through the University of Minnesota main campus). It is the second light-rail line in the region, after the Blue Line, which opened in 2004 and connects Minneapolis with the southern suburb of Bloomington. Construction on the Green Line began in late 2010. It opened to the public on June 14, 2014. The travel time between the downtown Minneapolis and downtown St. Paul stops is about 46 minutes. The entire line originally operated 24 hours a day, seven days a week, but as of 2019 trains are replaced by buses from 2 am to 4 am on weekdays. In 2018, the line carried a total of 13.8 million passengers. History Former streetcar and bus lines The route is a descendant of the Twin City Rapid Transit Company's St. Paul–Minneapolis streetcar line, also referred to as the Interurban line. Streetcars became practical along the route with the advent of electrification, and full service began along the route on December 9, 1890. In the 1950s, a decision was made to convert the streetcar system to buses. Streetcar service along the Interurban line ended in Saint Paul on October 31, 1953, and the route was the last to carry passengers in the city. Service continued a short while longer in Minneapolis, until November 28. However, due to fragmentary service elsewhere in Minneapolis, streetcars continued to use the tracks along University Avenue to reach the shops at Snelling Avenue in Saint Paul until June 1954. The route 16 bus was developed to replace the streetcar, and followed the route of the modern-day Green Line. Other parallel service included freeway express service on route 94 and limited-stop service to the University of Minnesota on route 50. Twin City Lines continued to privately operate buses until 1970, when the company was taken over by the Metropolitan Transit Commission, a precursor to Metro Transit. Proposals In 1972, the Regional Fixed Guideway Study for the Metropolitan Transit Commission (the forerunner