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Beaumaris Castle

A Scheduled Monument in Beaumaris (Biwmares), Isle of Anglesey (Ynys Môn)

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Latitude: 53.2648 / 53°15'53"N

Longitude: -4.0898 / 4°5'23"W

OS Eastings: 260712

OS Northings: 376238

OS Grid: SH607762

Mapcode National: GBR JN82.9BG

Mapcode Global: WH542.46QG

Entry Name: Beaumaris Castle

Scheduled Date: 5 November 1925

Source: Cadw

Source ID: 3319

Cadw Legacy ID: AN001

Schedule Class: Defence

Category: Castle

Period: Medieval

County: Isle of Anglesey (Ynys Môn)

Community: Beaumaris (Biwmares)

Built-Up Area: Beaumaris

Traditional County: Anglesey


The monument comprises the remains of a medieval castle built by King Edward I. Begun in 1295, Beaumaris Castle was the last royal stronghold to be built by the King in Wales and completed the chain of fortifications with which he had begun to enclose Gwynedd in 1277. Located on the south-eastern coast of the Isle of Anglesey, the castle controlled the new county of Anglesey and the Menai Strait that divides the island from the mainland. Beaumaris, meaning the ‘fair marsh’, was situated on level marshy ground not far from the water’s edge. The plan of the castle took full advantage of the flat site, unfettered by the natural constraints that shaped Conwy and Caernarfon Castles. It was built on the concentric – walls within walls – principle with four rings of formidable defences, including a wide water-filled moat with a dock that enabled the castle to be supplied directly from the sea.

The castle consists of an inner ward or courtyard which is more or less square, with a gatehouse north and south, and an outer ward of which the sides are not straight but angle outwards slightly in the middle. There are towers at each corner of the inner and outer wards, with buttressing towers in the outside centre of east and west inner walls, and traces of buildings in the inner ward. A moat once surrounded the castle and still exists on the north, west and half the south sides. There is a dock on the south where the moat now ends. The entrance is through the south gate, where cobbled floors survive. To a large extent the structure of the castle remains as it was constructed in 1295-1330. Domestic buildings within the inner ward have been removed; the eastern part of the moat has been filled in and the castle dock is no longer connected to the sea. The walls of the outer ward remain at their full height. The two gatehouses and the walls of the inner ward remain at the extent and height reached before construction ceased in 1330. Although minor sums of money continued to be spent on maintenance during the fourteenth and fifteenth centuries, there is no firm evidence of work of any consequence. Nevertheless, it was sufficiently complete to be garrisoned and besieged during the revolt of Owain Glyn Dŵr (about 1400-10). By 1539, however, the castle was reported to be in a ruinous state and by 1609 it was utterly decayed, so much so that when civil war broke out in 1642, Viscount Bulkeley is said to have spent £3000 on repairs to it in the royalist cause. But the eventual victory of parliament led in 1646 to the surrender of the castle to Major-General Thomas Mytton and by about 1660 some partial dismantling seems to have taken place.

The monument is of national and international importance for its potential to enhance our knowledge of medieval social, domestic and political life and warfare. This is reflected by its designation as a World Heritage Site.The scheduled area comprises the remains described and an area around them within which related evidence may be expected to survive.

Source: Cadw

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