A row of cannons pointed across to the Canadan boarder, circa 1880. The cannons were used to protect the Locks and Canals from attack and were fired every spring upon the arrival of the first ship through the locks and canals.

The federal government realized Sault Ste. Marie was an open target for sabotage and was a possible place to stage an invasion into the country and in 1866 ordered federal troops to occupy the base and return it to active duty. The fort buildings were rebuilt and remodelled. The federal troops were stationed here to protect the state locks and canals.