Llangollen Canal part of the London Midland and Scottish Railway soon afterwards. After the takeover by the London Midland and Scottish Railway, regular maintenance was often not carried out, and gradually the canals silted up, so that boats could not operate with full loads. Traffic declined, and was significantly affected by a breach that occurred at the Perry Aqueduct, about to the south of Frankton locks, which effectively closed the Montgomeryshire Canal to all traffic. Traffic beyond Frankton to Llangollen had ceased in 1937, and the Frankton to Hurleston section was not used after 1939. The London Midland and Scottish Railway obtained
Llangollen flow. The bridge was also widened in 1873 and again in 1968, using masonry which blended in with the older structure. It is a Grade I listed structure and a Scheduled Ancient Monument. On the outskirts of the town is Plas Newydd ("New Mansion" or "New Place"), from 1780 the home of the Ladies of Llangollen, the Honourable Sarah Ponsonby, Lady Eleanor Butler and their maid Mary Caryll. The Pillar of Eliseg is another old monument. There is an electoral ward of the same name. This ward includes Llantysilio community and has a total population taken at the 2011 census