The original Fort Preble was constructed in 1808 as a modified star design of earth, brick and stone. It was named in honor of Commodore Edward Preble of Portland and manned by three companies during the War of 1812. The fort became part of a system designed to guard the approaches to Portland Harbor. Portland Harbor Museum is located in the fort's Ordnance Machine shop which was completed in 1902.
Over the years several external buildings were built, new armament added and extensive rebuilding of the fort took place. In 1867, the granite exterior fort was completed.
In the photo Fort Preble and an opposing battery across the main ship channel were designed to deliver a cross fire on approaching enemy ships.
During the Civil War a few of its guns were mounted on a civilian steamer which thwarted a daring Confederate Navy raid on Portland Harbor.
Fort Gorges across the bay to the left of Spring Point Lighthouse was another unit of Portland's seaward defense network.
In 1896 Fort Preble was rebuilt as a Coast Artillery post. The brick buildings which survive as part of SMTC's campus were constructed in the first four years of the twentieth century.
The photo shows the mount for a 6-inch gun that was added in 1904.
The fort was manned throughout World War II and deactivated in 1950.
It was acquired by the State of Maine in 1952 and put to use as the home of Southern Maine Technical College.