I really liked this one in Peterborough, Ontario, Canada: https://en.wikipedia.org/wiki/Peterborough_Lift_Lock
Built as a real working lift lock (originally 1904), rather than as a tourist attraction. Powered by a little bit of extra water in one of the buckets to tip the balance and drive the pistons.
The wheel is a one-of-a-kind, but there are other ways of avoiding having a ladder of flood locks, see: https://en.wikipedia.org/wiki/Boat_lift
I really liked this one in Peterborough, Ontario, Canada: https://en.wikipedia.org/wiki/Peterborough_Lift_Lock Built as a real working lift lock (originally 1904), rather than as a tourist attraction. Powered by a little bit of extra water in one of the buckets to tip the balance and drive the pistons.