Boston Elevated Railway

The Boston Elevated Railway (BERy) was a streetcar and rapid transit railroad operated on, above, and below, the streets of Boston, Massachusetts and surrounding communities. Founded in 1894, it eventually acquired the West End Street Railway via lease and merger to become the city's primary mass transit provider. Its modern successor is the state-run Massachusetts Bay Transportation Authority (MBTA), which continues to operate in part on infrastructure developed by BERy and its predecessors.

Originally intended to build a short electric trolley line to Brookline, the West End Street Railway was organized in 1887. By the next year it had consolidated ownership of a number of horse-drawn streetcar lines, composing a fleet of 7816 horses and 1480 rail vehicles. As the system grew, a switch to underground pulled-cable propulsion (modeled after the San Francisco cable cars) was contemplated. After visiting Frank Sprague and witnessing the Richmond, Virginia system in action, WESR President Henry Whitney chose to deploy electric propulsion systems. A section of track was used to test the Bentley-Knight underground power line, but this was abandoned because of failures and safety concerns (especially after the electrocution of a team of horses in 1889). After competing in operational tests with the Sprague streetcar system, the Thomson-Houston company was chosen for system-wide deployment of overhead wires. The electrified rapid transit system was named an IEEE Milestone in Electrical Engineering in 2004.

The first electric trolley line built by the West End Street Railway was between Union Square, Allston and Park Square, downtown, via Harvard Street, Beacon Street, Massachusetts Avenue and Boylston Street. Trolleys first ran in 1889. The Green Line "A" Branch later served roughly the same purpose.

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