The First Church of Christ, Unitarian, also known as First Church of Lancaster and colloquially as "the Bulfinch Church", is a historic congregation with its meeting house located at 725 Main Street facing the Common in Lancaster, Massachusetts. The church's fifth meeting house, built in 1816, was designed by architect Charles Bulfinch, and was designated a National Historic Landmark in 1977, recognizing it as one of Bulfinch's finest works.

Lancaster is a town in Worcester County, Massachusetts, United States. Incorporated in 1653, Lancaster is the oldest town in Worcester County. As of the 2020 census, the town population was 8,441.