To cross a stream, highway or valley (wherever the hold off a result of a flight of locks at both aspect could be unacceptable) the valley is usually spanned by a navigable aqueduct – a well known illustration in Wales may be the Pontcysyllte Aqueduct (now a UNESCO Earth https://canalinfantil56654.blognody.com/41588211/how-much-you-need-to-expect-you-ll-pay-for-a-good-musica-infantil