Topsham, in Sagadahoc County, was incorporated on January 31, 1764 as the nineteenth town in Maine.
Recently Topsham has been a very rapidly growing community both in population (up 41% in 20 years) and in commercial development in the area of the Topsham Fair Mall, strategically located adjacent to Interstate 95. The Topsham Mill has been renovated to house a restaurant and other potential tenants.
The Cathance River flows through the town and into Merrymeeting Bay via Bowdoinham, with the 230-acre Cathance River Preserve and Watershed along the river in Topsham. The Bradley Pond Farm Preserve features 2½ miles of trails for hiking and cross-country skiing on a private working farm are maintained by the Brunswick-Topsham Land Trust.
