To cross a stream, highway or valley (wherever the hold off due to a flight of locks at both side would be unacceptable) the valley can be spanned by a navigable aqueduct – a famed case in point in Wales is definitely the Pontcysyllte Aqueduct (now a UNESCO Earth https://comprar-visualizacao-em-v00998.bloggerchest.com/37137906/the-fact-about-urso-fofo-that-no-one-is-suggesting