The canal was built in 1869 and has been renovated many times since then. Its history parallels Canada's, in many ways. Since the French trader Denys first settled the community in the 1700's it has seen battles between the French and English, extremely busy sailing vessel commerce from the Bras d'Or Lake to the world, and participated in all the major Canadian historical episodes. The lock is unique in North America for having double gates at each end. Because both ends of the lock can be lower than the water in the outside (lake or ocean), then one of the pair must always be convex facing the higher water. Tides in the Bras d'Or Lake are less than 1', but about 5' on the St. Peters Bay (ocean) side.