Twthill Castle
Twthill Castle is a small earthwork motte-and-bailey castle in the centre of Caernarfon in Gwynedd, North Wales, built at the command of William the Conqueror by Robert of Rhuddlan in the 1080s as part of the initial Norman advance into north Wales. The castle predates the great Edwardian fortification of Caernarfon by two centuries and represents the earliest phase of Norman fortification in this part of Wales, when earthwork mottes were quickly thrown up to establish control over newly seized territories. The motte stands within walking distance of the magnificent Caernarfon Castle, a UNESCO World Heritage Site, providing an interesting contrast between the earliest and most developed phases of Norman and Plantagenet castle construction in north Wales. The name derives from the Welsh Tŵr Twll meaning the hollow tower.