[1][2][3]: 81  By 1851, Somerville station was located 0.2 miles (0.32 km) to the east at Park Street, near the junction of the Harvard Branch Railroad.

[4][5] The station building was located on the north side of the tracks, just west of Park Street.

[6][7] Like Union Square and other local stops, Somerville was served primarily by Lexington Branch trains in the mid-19th century.

[8] Planning to eliminate the eleven remaining grade crossings in Somerville, five of which were on the Fitchburg Route mainline, began in 1900.

[9] In 1906, the city engineer proposed to raise 1.8 miles (2.9 km) of the line between Beacon Street and Somerville Avenue to eliminate the five level crossings, but that scheme was not adopted.