We really enjoyed the sightseeing boat ride we did on the Erie Canal a few years ago. The story of the "upside-down bridge" was very interesting; apparently the railroad built the bridge structure right down almost to the water level to make it impossible or at least very difficult to carry goods by barge. They were made to dismantle part of the structure to allow for boat passage.
The low-light of the trip was when a passenger sighted a body floating in the water as we returned to the dock. It was a man who had been missing for a couple of days.