This is an impressive sight both from “above”:https://i2-prod.dailypost.co.uk/incoming/article7330225.ece/ALTERNATES/s1227b/1384340.jpg and “below”:https://www.thetimes.co.uk/imageserver/image/methode%2Fsundaytimes%2Fprod%2Fweb%2Fbin%2F2db9e6ce-42b3-11e9-af00-ec1d0a9dead5.jpg?crop=2667%2C1500%2C0%2C0 . It is exhilarating either to cross on foot or by boat.
The late C18th was a time of peak building of canals, needed to carry raw materials and finished goods across the country. A canal was proposed to carry cargoes from the mineral rich coalfields of North East Wales. This was an ambitious project across difficult terrain. William Jessop and Thomas Telford were engaged to work on the project.
Their early plans were for a low level aqueduct across the River Dee with locks on either side, but this was abandoned in favour of Telford’s grand design: a cast iron trough mounted on stone pillars spanning the valley 126 feet below. The Pontcysyllte Aqueduct was born.
Despite considerable public scepticism, Telford was confident in the success of the plan as he had previously built a cast iron trough aqueduct on the Shrewsbury canal.
The Pontcysyllte Aqueduct was one of the first major feats of civil engineering undertaken by Telford, although his work was supervised by Jessop who was the more experienced canal engineer. It established Telford’s reputation as an engineer and designer.
The aqueduct took ten years to build, opening in 1805 and cost £47,000. It was originally built for horse drawn narrow boats and there is a tow path on one side of the canal. On the other side is an unfenced drop.
The aqueduct is a cast iron trough nearly 336 yards in length and five feet deep. It is only wide enough for one boat. The iron trough is mounted on iron arched ribs supported by eighteen hollow masonry piers.There is more information about its construction “here”:https://www.gracesguide.co.uk/Pontcysyllte_Aqueduct .
It linked the village of Froncysyllte to the south with Trevor to the north.
On one side was a tow path used by horses pulling the barges and is now a popular pedestrian walkway. On the other side is an unfenced drop.
Only part of the route was completed because revenue needed to complete it was never generated. Most major work ceased after the completion of the Pontcysyllte Aqueduct. It had been intended to extend the canal to Wrexham where a feeder lake had been built to provide water for the canal.
Trevor Basin became the northern terminus with a feeder channel bringing water from the River Dee at Horseshoe Falls near Llangollen near Llangollen, which maintained water levels and continuous flow of water.
Commercial traffic on the canal greatly declined after a waterway breach near Newtown, Powys in 1936. By 1939 boat movements across the aqueduct to Llangollen had ceased. The canal was formally closed to navigation in 1944.
Although there was no boat traffic on the canal, it survived as it was required as a water feeder for the remainder of the Shropshire Union Canal. The aqueduct also supplied drinking water to a reservoir at Hurleston. The Mid & South East Cheshire Water Board agreed to maintain the canal securing its future
In the latter half of the 20th century, leisure boating traffic began to rise and this is one of the more popular stretches of canals.
The Aqueduct is a World Heritage site and rightly so.