To cross a stream, road or valley (where by the delay caused by a flight of locks at either facet would be unacceptable) the valley can be spanned by a navigable aqueduct – a renowned illustration in Wales is the Pontcysyllte Aqueduct (now a UNESCO Environment Heritage Website) through https://chancebkqtw.xzblogs.com/77535864/the-smart-trick-of-musica-infantil-that-no-one-is-discussing