Caerphilly Castle is a medieval castle in the centre of Caerphilly town in south Wales. It is the largest castle in Wales and the second largest in Britain.
The Pontcysyllte Aqueduct is an aqueduct in Wrexham County Borough in north east Wales. Completed in 1805, it is the longest and highest aqueduct in Britain. The Pontcysyllte Aqueduct is listed as a UNESCO World Heritage Site.
The Castles and Town Walls of King Edward in Gwynedd are a UNESCO protected site in Gwynedd, Wales. Four castles related to the reign of King Edward I of England were proclaimed collectively as a World Heritage Site.