Construction of Fort Mississauga began in 1814. It was meant as a counter position to the American Fort Niagara on the opposite bank of the Niagara River. The fort was built with an irregular star shape which features a stone “Martello-type” tower. The tower and magazines built into the earthworks incorporated stone and brick rubble salvaged from the town and from the nearby lighthouse. After the War of 1812, the fort was left to deteriorate and was disarmed in 1856.
In later years, Fort Mississauga was used as a summer training camp for Canadian military. The site was also used for recreational purposes, including strolling, picnicking and golfing. A nine-hole golf course has existed on the site since the late 1870s. It is currently a National Historic Site.