Beaumaris Castle
Uncompleted Medieval Concentric Castle in Wales

Beaumaris Castle is a great unfinished masterpiece. It was built as one link of the 'iron ring' of North Wales castles by the English monarch Edward I, to stamp his authority on the Welsh. Begun in 1295, this was the last and largest of the castles to be built by King Edward I in Wales during his programme of royal castle building.

The castle is possibly the most sophisticated example of medieval military architecture in Britain and has few equals anywhere in the world. It is surrounded by a water-filled moat with a seaward entrance protecting a tidal dock and allowed supply ships to sail right up to the castle.

Its symmetrical concentric design, involving four successive lines of fortifications, represented the state of the art for the late 13th century. This outstanding castle, built in Gritstone, is a World Heritage inscribed site.

Unesco World Heritage Site

Unesco name of World Heritage site: Castles and Town Walls of King Edward in Gwynedd (added in 1986)

Justification for Inscription: "The four castles of Beaumaris, Conwy, Caernarfon, Harlech and the attendant fortified towns at Conwy and Caernarfon are the finest examples of late 13th century and early 14th century military architecture in Europe, as demonstrated through their completeness, pristine state, evidence for organized domestic space, and extraordinary repertory of their medieval architectural form.

The castles as a stylistically coherent groups are a supreme example of medieval military architecture designed and directed by James of St George, King Edward I of England’s chief architect, and the greatest military architect of the age.

The extensive and detailed contemporary technical, social, and economic documentation of the castles, and the survival of adjacent fortified towns at Caernarfon and Conwy, makes them one of the major references of medieval history.

The castles of Beaumaris and Harlech are unique artistic achievements for the way they combine characteristic 13th century double-wall structures with a central plan, and for the beauty of their proportions and masonry.

Criterion (i): Beaumaris and Harlech represent a unique achievement in that they combine the double-wall structure which is characteristic of late 13th century military architecture with a highly concerted central plan and in terms of the beauty of their proportions and masonry. These are the masterpieces of James de St George who, in addition to being the king’s chief architect, was constable of Harlech from 1290 to 1293.

Criterion (iii): The royal castles of the ancient principality of Gwynedd bear a unique testimony to construction in the Middle Ages in so far as this royal commission is fully documented. The accounts by Taylor in Colvin (ed.), The History of the King’s Works, London (1963), specify the origin of the workmen, who were brought in from all regions of England, and describe the use of quarried stone on the site. They outline financing of the construction works and provide an understanding of the daily life of the workmen and population and thus constitute one of the major references of medieval history.

Criterion (iv): The castles and fortifications of Gwynedd are the finest examples of late 13th century and early 14th century military architecture in Europe. Their construction, begun in 1283 and at times hindered by the Welsh uprisings of Madog ap Llywelyn in 1294, continued until 1330 in Caernarfon and 1331 in Beaumaris. They have only undergone minimal restoration and provide, in their pristine state, a veritable repertory of medieval architectural form: barbicans, drawbridges, fortified gates, chicanes, redoubts, dungeons, towers, and curtain walls."