To cross a stream, road or valley (the place the hold off because of a flight of locks at possibly aspect can be unacceptable) the valley could be spanned by a navigable aqueduct – a well-known case in point in Wales is definitely the Pontcysyllte Aqueduct (now a UNESCO https://canal-infantil10998.aioblogs.com/89863746/indicators-on-canal-infantil-you-should-know