We did take the boat tour in Peterborough. It took us through two locks which are part of the Trent Severn Waterway that links Lake Ontario to Georgian Bay. The first lock was your typical kind where the boats come in and they fill the basin with water. The second was the lift lock. I'll show you more of it tomorrow, it's quite something!
I'm linking this post up to Sunday Bridges. Click on the link to see more bridges from around the world.