This is the highest navigable aqueduct ever built and is recognised as a masterpiece of civil engineering. Built by Thomas Telford and William Jessop between 1795 and 1808, it forms part of an 11-mile canal system that was recently placed on the World Heritage list of sites of Outstanding Universal Value. You can go across by barge or on foot, but be careful - the River Dee below seems an awfully long way down!
Trevor Basin, Llangollen, Denbighshire