Beaumaris Castle, located in Beaumaris, Anglesey, was built as part of Edward I's campaign to conquer North Wales. Begun in 1295, it was designed by James of St. George. Beaumaris is now regarded as the most architecturally perfect castle in Britain, and has been designated as a World Heritage site.
Beaumaris castle faced Garth Celyn on the opposite shore of the Menai Strait, and was deliberately positioned, together with Conwy castle and Caernarfon castle at either end of the Menai Strait, to overshadow the Welsh royal home and centre of resistance to the English forces.
Beaumaris (beau mareys - fair marsh) Castle was the last of Edward I's fortresses in North Wales. However, the fortress was never fully completed as finances and material ran out, as Edward turned his attentions towards Scotland before it reached its full height.
During the course of construction, Edward ordered that the all the inhabitants of nearby Llanfaes be evicted from their homes, and relocated on the far side of the island at Newborough. All pleas against this action were dismissed.
The King's architect, Master James of St George, brought all his experience to bear when constructing Beaumaris: its defences and lines of supply are superbly thought out. It was designed using a concentric plan, with its inner ward completely surrounded by an outer ward. The castle has a tidal dock which allowed it to be supplied directly from the sea, and it is surrounded by a water-filled moat. The defences also include numerous ingeniously sited arrow slits, and the entrances are protected by murder holes from which substances such as hot oil could be poured over enemy forces. Any attack on Beaumaris Castle would have to overcome 14 separate obstacles and four lines of fortifications made possible by the 'walls within walls' design.
The plan of the castle is basically square, and shares much in common with Caerphilly and Harlech. The inner ward is rectangular, with a round tower at each corner. On the north and south side are two massive gatehouses following the typical pattern of two D-shaped towers flanking the gate passage, while two more D-shaped towers defend the east and west walls. The great hall and other domestic buildings were to be constructed within this inner ward.
Surrounding the inner bailey, in accordance with the concentric ideal, is an outer wall defended by many towers and its own two gatehouses. These were positioned out-of-line with the inner gatehouses so that attackers would not have a straight path through the gates. The dock wall extends from the south wall near the gatehouse, and also serves as a firing platform to defend that gateway. Unlike the simple outer walls at Caerphilly and Harlech, the walls here are very thick and have passages in them that allow defenders access to protected arrow slits.
Though the plan was nearly perfect, and the castle is well-preserved, it can never be seen in as its architect intended as the building was never completed. The Welsh conquest was basically complete at the time of construction, and the immense cost of building such a massive fortress was seen as unnecessary expense when finances were needed to fund the campaigns against the Scots.. None of the towers of the inner ward, including both great gatehouses, were completed to full height and many buildings of the inner ward were left unfinished. However, the outer walls were crenelated, and the castle did not suffer slighting during the Civil War (like so many others), so the extant castle is still an impressive sight.
The castle is run and managed by Cadw, (the Welsh Assembly Government's agency for historic monuments), which provides visitors with a guidebook, an exhibition, gifts and souvenirs, good disabled access and picnic facilities in the castle grounds. Ducks and swans swim on the castle moat.