The complex includes four major structures and seven smaller ones, on about 14 acres (5.7 ha) of land along the Salmon Falls River.

They were built between about 1840 and the mid-1860s, and have an unusual architectural unity, for additions made to the buildings were done with attention to matching design elements from the existing structures.

That mill was eventually purchased by a partnership including Amos Lawrence, a major Boston, Massachusetts textile industrialist.

Eventually incorporated as the Salmon Falls Manufacturing Company, Lawrence and his associates built a new mill (the present Number 2 building), and introduced new technology perfected at Lowell, Massachusetts including the turbine.

[2] The historic district consists of eleven buildings and structures, most of which are set between Front Street and the river.