The Highland branch, also known as the Newton Highlands branch, was a suburban railway line in Boston, Massachusetts. It was opened by the Boston and Albany Railroad in 1886 to serve the growing community of Newton, Massachusetts. The line was closed in 1958 and sold to the Metropolitan Transit Authority (MTA), the predecessor of the current Massachusetts Bay Transportation Authority (MBTA), which reopened it in 1959 as a light rail line, now known as the D branch of the Green Line. The first section of what became the Highland branch was built by the Boston and Worcester Railroad between Boston and Brookline in 1848. The Charles River Branch Railroad, a forerunner of the New York and New England Railroad, extended the line to Newton Upper Falls in 1852. The B&A bought the line in 1883 and extended to Riverside, rejoining its main line there. The MTA electrified the line when it rebuilt it for light rail use. The conversion of the Highland branch into a light rail line was pioneering in several ways. Amid a backdrop of failing private passenger service in the United States, it was the first time a government entity in that country had assumed full responsibility for losses on a route. It was also the only example of converting an extant commuter rail line to light rail use. History Precursors What became the Highland branch was built in stages. The initial segment was the Boston and Worcester Railroad's Brookline branch, which opened on April 10, 1848. This line stretched from a junction with the Boston and Worcester main line south of Governor Square southwest to the current location of the Brookline Village station in Brookline, with an intermediate station at Longwood Avenue. Construction costs were roughly $42,000. Brookline had previously only been reachable by road (horsecar service on what is now Huntington Avenue did not begin until 1859), and the branch was quickly a success. Based on this success, the Charles River Branch Railroad was founded in 1849 to extend service west from Brookline. Beginning in 1851, the railroad built from Brookline to Newton Upper Falls. This extension opened in November 1852, at a cost not exceeding $253,000. The line was further extended to Great Plains (later part of Needham) the next year, and to Woonsocket, Rhode Island in 1863. The Charles River Branch Railroad also constructed its own track parallel to the Brookline branch. From