The Llangollen Canal (Welsh: Camlas Llangollen) is a navigable canal crossing the border between England and Wales. The waterway links Llangollen in Denbighshire, north Wales, with Hurleston in south Cheshire, via the town of Ellesmere, Shropshire. The name, which was coined in the 1980s, is a modern designation for parts of the historic Ellesmere Canal and the Llangollen navigable feeder, both of which became part of the Shropshire Union Canals in 1846.
The Ellesmere Canal was proposed by industrialists at Ruabon and Brymbo, and two disconnected sections were built. The northern section ran from Ellesmere Port on the River Mersey to Chester, where it joined the Chester Canal, and opened in 1795. Work on the southern section began at Frankton, with a line southwards to Llanymynech, and subsequently, a second section was built westwards towards Trevor. This involved crossing the Afon Ceiriog and the River Dee, which was achieved by building two vast aqueducts, using iron troughs to contain the water. The Ceiriog was crossed at Chirk, and Chirk Aqueduct opened in 1801, to exploit local supplies of iron and coal. The canal then passed through Chirk Tunnel, and reached the southern end of Pontcysyllte Aqueduct in 1802, which was not completed until 1805. To join the two halves up, a heavily engineered route from Trevor Basin via Ruabon and Brymbo to the River Dee at Chester was planned, but very little of it was built. Instead, the present route from Frankton to Hurleston Junction on the Chester Canal was constructed, and opened in 1805. As the route never reached the water reservoir at Moss Valley, Wrexham (built in 1786), a navigable feeder was built to Llantisilio where the Horseshoe Falls weir was constructed on the River Dee to supply the canal.