Cotton textile mills migrated to Maine from Massachusetts beginning in the 1820s. The major site for cotton textile manufacturing was Lewiston on the Androscoggin River, the most northerly of the Waltham-Lowell system towns (factory towns modeled on Lowell, Massachusetts). The twin cities of Biddeford and Saco, as well as Augusta, Waterville, and Brunswick also became important textile manufacturing communities. These mills were established on waterfalls and amidst farming communities as they initially relied on the labor of farm-girls engaged on short-term contracts. In the years after the Civil War, they would become magnets for immigrant labor.