This canal was completed in 1805 as part of a plan to link Liverpool and Bristol but the full project was never completed. This is probably the most popular canal in Britain and it features the Pontcysyllte Aqueduct – the highest and biggest in the British Isles. The work of Thomas Telford and William Jessop, the aqueduct is a Scheduled Ancient Monument, a candidate for World Heritage Status and a Grade 1 listed structure, a waterways wonder and one of the wonders of Wales. The aqueduct linked Llangollen with the rest of the Shropshire Union canal system. It originally carried coal from local mines and supplied water from Horseshoe Falls into the rest of the Shropshire Union Canal. The aqueduct still carries over 50 million litres of water each day to supply water to southern Cheshire and the canal therefore escaped the canal closures in the area.