To cross a stream, street or valley (the place the delay due to a flight of locks at either facet will be unacceptable) the valley may be spanned by a navigable aqueduct – a popular example in Wales is the Pontcysyllte Aqueduct (now a UNESCO World Heritage Site) through https://musica-infantil13277.total-blog.com/the-ultimate-guide-to-urso-fofo-62416125