Lexington and Arlington Railroad

The Lexington and West Cambridge Railroad was a railroad company chartered in 1845 and opened in 1846, that operated in eastern Massachusetts, U.S.A. It and its successors provided passenger service until 1977 and freight service until 1980 or early 1981.

A single track line was constructed in 1845-46, connecting Lexington Center to the Fitchburg Railroad (now the MBTA Fitchburg Line) in West Cambridge (near the site of the modern Alewife Station). When the separate town of West Cambridge changed its name to Arlington in 1867, the railroad was also renamed, as the Lexington and Arlington Railroad.

The Boston and Lowell Railroad purchased the line in 1870 and built a new connection (most of which would constitute a major portion of the later Fitchburg Cutoff) to their main line at Somerville Junction. The connection, from what is now the Magnolia Field-Varnum Street area in Arlington, ran through North Cambridge and West Somerville (Davis Square); a station was located at Somerville Junction, commemorated by a park near what are now Centre and Woodbine Streets. The Boston and Lowell created a subsidiary, the Middlesex Central Railroad, to build an extension from Lexington to Bedford and then Concord Center (Lowell Road), which opened in 1873. The Lowell Road station was adjacent to today's Minuteman National Historical Park. A 2.5-mile (4.0 km) extension from Concord Center to Concord Prison (Reformatory Station on Elm Street) would give the name Reformatory Branch to the Bedford-Concord segment in 1879. The branch continued another half mile further west to a junction (called "Concord Junction" or "Middlesex Junction" per different sources) with the Nashua, Acton & Boston Railroad and other rail lines.

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