Portal:Trains/Selected article/Week 4, 2015

The Green Line is a light rail system run by the Massachusetts Bay Transportation Authority (MBTA) in the Boston, Massachusetts, metropolitan area. It is the oldest Boston subway line, with tunnel sections dating to 1897. It runs underground through downtown Boston, and on the surface on several radial boulevards and into inner suburbs. With a daily weekday ridership of 210,000 in early 2014, it is the second most heavily-used light rail system in the country. The line was assigned the green color in 1967 during a systemwide rebranding because several branches pass through sections of the Emerald Necklace of Boston. The four branches are the remnants of a large streetcar system, which began in 1856 with the Cambridge Horse Railroad and was consolidated until the Boston Elevated Railway several decades later. The Tremont Street Subway—the oldest subway tunnel in North America—opened its first section on September 1, 1897, to take streetcars off overcrowded downtown streets; it was extended five times over the next five decades. The streetcar system peaked in size around 1930 and was gradually replaced with trackless trolleys and buses, with cuts as late as 1985. A new branch opened on a converted commuter rail line in 1959; the Green Line Extension project will add two new branches into Somerville and Medford in 2017 and 2019.