The view from the bridge
My most interesting experience was crossing the Pontcysyllte aqueduct on the Llangollen canal. The canal is carried in an 8' wide trough made of 1/4" plate iron. on one side is a path (originally for tow horses), with a rail.
On the other side, the lip of the trough is 4-6" above water level (below deck level of the boat) and you look straight down past an invisible edge at a 126' drop!
