Pontcysyllte Aqueduct
Pontcysyllte Aqueduct is a marvel of civil engineering that continues to amaze with its dizzying feat of carrying a canal high over a river, says Maria Hodson
Wrexham
Spanning the River Dee between Trevor and Froncysyllte, the Pontcysyllte Aqueduct and its canal system are a World Heritage Site. The wonder of this structure is conveyed by its other, more poetic name. Behold ‘the Stream in the Sky’, the tallest navigable aqueduct in the world.
This moniker came from Sir Walter Scott, who was not alone in paying tribute. Writer Washington Irving called it “that stupendous work”; while mathematician Charles Dupin described it as “something enchanted, on its high slender pillars, a work of architecture, elegant and unadorned”.
The last stone of this bold construct was laid in 1805, completing an ingenious design by Thomas Telford and fellow engineer William Jessop. Telford’s name rings like a iron bell through Britain’s industrial past; history has been more neglectful of William Jessop (partly due to Telford’s omissions), but Jessop’s contribution ought not be overlooked. The two devised an ambitious solution to the problem presented by local geography. Here, in the lush Dee valley, were industrial riches galore – rich coal seams, limestone quarries and coal. But how to get such resources to the industrial towns of the Midlands? Transport by road was slow and expensive. Canals were cost-effective, speedy and efficient. But the great Dee was in the way. The answer – a stream in the sky.
HIGH AND MIGHTY
Today it stands, 39m high, carrying the Llangollen canal over the rushing river below. Holding 1.5 million litres of water, the cast-iron trough is 307m long and twice as wide as it is deep. Both the canal and the footpath to its side feel precariously narrow – cyclists peer nervously at the canal water as they wheel their bikes past pedestrians who press themselves, white-faced, against the railings. Still visible on these railings are the grooves made by the ropes of horse-drawn narrowboats.
Amazingly, the other edge, between the canal and the drop, has no railing, which is surely a hair-rising prospect for any navigators standing at the helm of their narrowboats.
The aqueduct has a noble look – 18 stone piers, partly hollow and tapered to keep weight down and to allow workers to build from within, rise from river to sky, spanned by 19 cast-iron arches of 13.7m in length. The edifice was built by 500 men using basic wooden scaffolding, primitive cranes and muscle power. Just one man fell during the construction – rare in an era of poor workplace safety and frequent deaths.
Although a respected architect and builder, Telford– incredibly – had no experience of waterways when appointed Ellesmere Canal Company’s general agent in 1793. Jessop, however, was Britain’s most experienced canal builder, and remained senior figure on the project. Together they devised the Llangollen canal network, cutting across rugged terrain and pioneering the use of iron in canal building. The full scope of the project was never realised, but its achievements remain outstanding.
The town of Llangollen is a lovely place from which to enjoy the wonders of the canal, and is replete with charming guesthouses and restaurants. You can reach the aqueduct by various means – drive, cycle the canal path, or hop on a narrowboat trip to experience the thrill of crossing. If, like me, you’re keen to stretch your legs on a long hike and explore the wider area, a great option is a long circular walk via Castell Dinas Bran to the Pontcysyllte Aqueduct and back via the Llangollen Canal.
1 CROW CLIMB
Start at the Tea Room by
Llangollen Wharf, cross the stone bridge over the canal and follow the signs uphill for Castell
Dinas Bran. Go through a gate on the right with a sculpture of a black crow – the totems of
“IT HAS A NOBLE LOOK – 18 STONE PIERS RISE FROM RIVER TO SKY, SPANNED BY 19 CAST-IRON ARCHES”
Castell Dinas Bran (bran in Welsh is crow; you’ll spy these feathered guardians circling the ruins). Weave up through gorse and heather to the summit, passing hovering kestrels.
2 KING OF THE CASTLE
Mounting what was once a prehistoric hill fort, the stone ruins are from the short-lived Castell Dinas Bran, built in 1260 but razed in 1277. Scan the horizon to see Eglwyseg limestone escarpment off to the north, the Llantysilio Mountains to the west, the Berwyn Mountains dominating the view south and, to the east, the viaduct carrying the railway over the Dee.
Head north-east from the summit to exit Castell Dinas Bran and turn left briefly on to the road before turning right on to Panorama Walk, part of Offa’s Dyke Path. This aptly named road wends through rich limestone and spectacular views of the Dee valley.
3 INTO THE WOODS
Continue along Offa’s Dyke
Path, which is clearly marked and very easy to follow, as the views open up beautifully to your right, before entering the peaceful mixed woodland of
Trevor Hall Woods. Pass between dappled trees to emerge on briefly to a road until it meets the A539. Turn left along here for a short distance before turning right into the town of Trevor, along the canal to Trevor Basin.
4 ALONG THE AQUEDUCT
When Pontcysyllte Aqueduct opened in 1805, Trevor Basin was transformed into a hub of narrowboats shifting coal, iron, limestone, bricks and tiles. Today it is a quieter hub of leisure boats. Here, admire the museum and walk the length of the aqueduct. Marvel at its height, the rushing river below and the narrowboats crossing the seemingly perilous waterway. Telford and Jessop’s creation is a fine structure without ostentation, just the simple elegance of engineering prowess.
5 RETURN CROSSING
Retrace your steps, following signs for Llangollen.
6 CALM BY THE CANAL
Take the canal footpath all the way back to Llangollen, a glorious flat stroll with water either side – the tranquil canal to your right, the roaring Dee on your left. Note the craggy rock from which the canal was gouged arduously by the ‘navvies’ who built it.
7 LLANGOLLEN END
You’re back! If you feel wildly energetic, pass Llangollen to the Horseshoe Falls, the start of the Shropshire Grand Union Canal, where every day, 12 million gallons of water are drawn in from the River Dee to supply water to the canals. If not (and who could blame you?), end at Llangollen for well-deserved sustenance and to admire this delightful town on the Dee.
FURTHER READING Man of Iron: Thomas Telford and the Building of Britain by Julian Glover (see page 103)