To cross a stream, highway or valley (the place the delay attributable to a flight of locks at either side would be unacceptable) the valley is usually spanned by a navigable aqueduct – a famed illustration in Wales would be the Pontcysyllte Aqueduct (now a UNESCO Planet Heritage Website) https://trentonygluy.ambien-blog.com/43731969/musica-infantil-for-dummies