Chelmsford is a town in Middlesex County, Massachusetts in the United States. It is within the traditional homeland of the Pennacook, whose descendants are members of the Abenaki First Nation. It is located 24 miles (39 km) north-west of Boston and, bordering on the city of Lowell, is part of the Greater Lowell metropolitan area. Besides Lowell on its north-east, Chelmsford is surrounded by four towns: Tyngsborough to the north, Billerica to the south-east, Carlisle to the south, and Westford to the west. Chelmsford is bordered by two sizeable rivers: the Merrimack River to the north and the Concord River to the east.
Named after Chelmsford, Essex, England, the town was incorporated in May 1655 by an act of the Massachusetts General Court. When Chelmsford was incorporated, its local economy was fuelled by lumber mills, limestone quarries and kilns. The farming community of East Chelmsford was incorporated as Lowell in the 1820s; over the next decades it would go on to become one of the first large-scale factory towns in the United States because of its early role in the country's Industrial Revolution. Chelmsford experienced a drastic increase in population between 1950 and 1970, coinciding with the connection of U.S. Route 3 in Lowell to Massachusetts Route 128 in the 1950s and the extension of U.S. Route 3 from Chelmsford to New Hampshire in the 1960s.
The town has one public high school – Chelmsford High School, which is ranked among the top 500 schools in the nation – as well as two middle schools, and four elementary schools. In 2011, Chelmsford was declared the 28th best place to live in the United States by Money magazine.
Chelmsford has a population of over 33,802 people. Chelmsford also forms part of the Greater Lowell metropolitan area which has a population of over 312,447 people.