This line started out in 1846 as the Lexington and West Cambridge Railroad, which connected its namesake towns in Massachusetts. It continued under the name of Lexington and Arlington Railroad in 1867, was purchased by the Boston and Lowell Railroad in 1870, and by 1873, under its Middlesex Central Railroad subsidiary, had reached as far west as Concord. The Boston and Maine Railroad purchased the entire line outright in 1887.

Passenger service remained strong through the early- to mid-1900s, and the Massachusetts Bay Transportation Authority acquired the line to continue commuter service, with B&M retaining trackage rights along the line for freight service. A passenger train stranded at the Bedford Station during a snow stored spelled the end of MBTA's passenger service along the line in 1977, and freight service was discontinued soon after in 1981.

The line was abandoned in segments over time. The furthest western reaches of the line in Concord were abandoned in 1926; and the section between Bedford and Concord seeing abandonment in 1962. Rail service continued along the line to Bedford until the last freight train in 1981. Finally, in 1992, the entire line was rail-banked, and the right-of-way now serves as the Minuteman Bikeway today.