Fort Popham is a coastal defense land battery at the mouth of the Kennebec River in Phippsburg, Maine. It is located in sight of the short-lived Popham Colony and, like the colony, named for George Popham, the colony’s leader.
Construction of Fort Popham was authorized in 1857, but did not begin until 1862 when the Union became nervous about the Confederacy’s newest naval ship design, the ironclad warship, and its possible effect on Bath Iron Works and Maine’s capital city of Augusta, which is located less than 20 miles up the Kennebec River. The fort was built from granite blocks quarried on nearby Fox Island and Dix Island. It had a 30-foot-high wall facing the mouth of the Kennebec River had was built in a crescent shape, measuring approximately 500 feet in circumference.
Fort Popham’s armament consisted of 36 cannons arranged in two tiers of vaulted casements. Each cannon weighed roughly 25 tons and fired solid shot, each weighing almost 480 pounds. The back side of Fort Popham was built with a low moated curtain containing a central gate and 20 musket ports.
In 1869 construction at Fort Popham stopped before the fortification was completed. The fort was garrisoned again after additional work was performed during the Spanish-American War and World War I. Construction of Fort Baldwin on the headland above Fort Popham began in 1905 with longer-range guns, which eventually rendered Fort Popham obsolete. The fort is now open to the public as a park.