Station A-1 is located on State Highway 125 near the intersection of State Highway 28 in Andover. The barracks primary patrol area is Interstate 93 and later included Interstate 495; a coverage totaling over 222 square miles within 12 cities and towns.
Station H-5, SP Brighton Barracks, patrols mostly DCR and state roadways and parks along the Charles River in the Boston and Cambridge areas. It was formerly know as the Upper Basin District because it was located near the upper basin area of the Charles River.
The Brookfield Barracks is located in Central Massachusetts where Route 9 is the major east/ west thoroughfare and prior to the construction of the Massachusetts Turnpike was the main artery between Boston and New York.
State Police Charlton was built in 1957 and is a concrete/stone façade two-story building located off the eastbound lane of the Massachusetts Turnpike at the 79mm in Charlton. Geographically, SP Charlton was strategically located in the center of the Massachusetts Turnpike exactly half way between the Weston and Westfield barracks. After the end of the barracks system in 1971, the station was used primarily as a reporting location for officers assigned to the central section.
Up until the end of the 1970's, Troopers working on the Massachusetts Turnpike not only performed patrol and enforcement functions, they also transported the injured to hospitals by using station wagons as cruisers that were equipped with gurneys. During the winter of 1992 the barracks opened on a full time basis. In December of 1999, the station was redesigned after the rear tandem wheels' broke loose from a Tractor Trail Unit and came crashing through the front window of the station. SP Charlton has become one of the busiest traffic areas due to the high volume of truck traffic and its close proximity to interstates 84, 290, 395 and 495.