Fort Wellington was commissioned by the British government and built in 1812. Ramparts surrounded by dry ditches and fences enclosed the area, leaving only one entryway on the north facade. Inside, the wooden buildings were designed to be hidden behind the ramparts when looking from the exterior. There were two 24-pounder iron cannons mounted on the south corners of the ramparts, and their range allowed them to fire on any ships passing in front of the fort, and even extended as far as buildings across the river in New York.
During the rebellion of 1837, the Crown commissioned a reconstruction of the fort, and the modern Fort Wellington buildings have survived from this time. The main blockhouse is a three-storey stone structure completed in 1839. It functioned as the cookhouse, guardhouse, latrine, and officer’s quarters. Two 12-pounder cannons were added on the north corners of the ramparts, and a 36-pounders was installed over the gate.
In 1920, Fort Wellington was named as a National Historic Site of Canada. During the summer, Fort Wellington is open for tours of the restored buildings, led by uniformed guides. There is a military museum on the third floor of the blockhouse, and a new visitor centre was built in 2012. The cannons are still functioning, and visitors can sign up for a day-course with a member of the cannon crew that culminates in firing the cannon.