Pontcysyllte Aqueduct
The work of Thomas Telford and William Jessop, the aqueduct is a Scheduled Ancient Monument, a World Heritage Site 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.