Beaumaris Castle was the last great fortress built by Edward I, begun on Anglesey in 1295 to project English power across the sea lanes of North Wales. Never fully completed, its concentric design with multiple moats and walls remains the pinnacle of medieval military architecture.
Strategically located on the Isle of Anglesey along the coast of North Wales, Beaumaris Castle occupied a vital position from which Edward could control the sea route from North Wales towards Ireland.
Why was Beaumaris Castle built?
After defeating the Welsh prince Llywelyn ap Gruffudd in 1282, Edward embarked on building a formidable chain of castles across North Wales to consolidate his victory. As the last of these fortresses constructed, Beaumaris was intended to be the crowning achievement: an impregnable stronghold and supply base from which royal power could be projected across the entire region. However, the ambitious scale of construction proved too much to complete, and Beaumaris never reached its full intended size before building stopped in 1330.
Nonetheless, the awe-inspiring ruins still convey a vivid sense of Edward's iron ring of castles enclosing Wales. As one of the great medieval fortresses of Britain, Beaumaris has an enduring legacy that continues to attract visitors exploring the history of castles in Wales.
Building Beaumaris Castle
Construction on Beaumaris Castle began in 1295 under the direction of Master James of St George, the foremost castle architect of the age. As Edward I's final campaign brought the north coast of Wales under English control, a huge effort was undertaken to build Beaumaris and consolidate the king's victory.
Thousands of skilled workers were recruited, not just from England but from across Europe. Transporting the necessary stone and supplies required a massive logistical effort. Funding the ambitious project imposed a huge financial burden at a time when Edward was running low on money after his successive Welsh campaigns.
Beaumaris was meticulously designed as a concentric castle with multiple defensive walls and moats. The inner ward contained the main living quarters and great hall for the king and his retinue. The outer walls had 12 towers spaced at intervals where archers could defend against attack. Three huge gatehouses controlled access, with a dock allowing ships to resupply the garrison during a siege.
Despite the resources poured into its construction, Beaumaris was never fully completed according to the original plan. The expense had drained the king's coffers, and political priorities shifted after Edward's conquest of Wales was complete. By 1330, construction had halted with the fortifications still lacking their full intended size. Nonetheless, Beaumaris remained a formidable stronghold on the strategic sea approach to North Wales.
Beaumaris Castle's Design Features
Beaumaris Castle was designed by Master James as a concentric castle with multiple lines of defence. The inner ward contained the luxurious living quarters and great hall, with a moat and outer walls protecting them. Between the inner and outer walls was an additional moat and killing ground where defenders could rain down missiles and arrows on attackers.
The outer walls had twelve large towers spaced at intervals so archers had overlapping fields of fire to defend the entire perimeter. Arrow slits, murder holes, battlements, and wall walkways allowed defenders to attack besiegers from all directions. Three huge gatehouses controlled access, each with a drawbridge, portcullis, murder holes, and multiple doors.
A dock was built allowing ships to resupply Beaumaris during a siege or blockade. The sea entrance could be closed by a massive iron chain drawn across it. Having access to the sea was a key advantage of the location, as ships could still reach the castle even when the land approaches were blocked.
The concentric design provided multiple fallback positions so defenders forced back from the outer fortifications still had the formidable inner castle keep to retreat to. With its excellent natural defences from the sea and Master James's clever architecture, Beaumaris was designed to be an impregnable fortress and symbol of English power.
Later History and Decline of Beaumaris Castle
Although intended as Edward's last great castle, Beaumaris was never fully completed. The enormous cost had drained the royal treasury, and construction halted in 1330 before reaching the planned size. Nonetheless, it remained a formidable fortress along the sea approach to North Wales.
During the rebellion of Owain Glyndŵr in the early 15th century, Welsh forces seized control of Beaumaris for several years before it was retaken by the English crown.
Gradually the castle declined in military significance after the Tudor dynasty and the beginning of the early modern era. By the 1600s, Beaumaris was already seen as an antiquated medieval fortress, lacking relevance for newer forms of warfare.
The castle was briefly garrisoned again during the English Civil War in the 1640s, but swiftly fell into disuse and disrepair after that conflict. Lacking a military role, Beaumaris became a local prison and many buildings inside the castle were stripped for usable building materials. By the 18th century, the ruined castle with its romantic, decaying architecture began attracting artists.
Renewed interest during the Victorian era led to excavations and conservation efforts at Beaumaris. Tourism was growing, and the castle became part of the circuit of medieval castles that visitors explored in North Wales. The substantial ruins still evoked the conquered Welsh kingdom of Gwynedd and the mighty castle-building achievements of King Edward I.
Beaumaris As A Tourist Destination
Today Beaumaris Castle forms part of the historic castles route that makes North Wales such a popular tourist destination. As one of the famous castles built by Edward I during his conquest of Wales in the late 13th century, Beaumaris receives many visitors eager to see its history.
While never fully completed, the castle's extensive ruins still allow people to marvel at the scale of medieval architecture and imagine what the completed fortress must have looked like. The huge stone walls, towers, and gatehouses give a vivid impression of English power and dominance over Wales. Reenactments of medieval life held at the castle immerse visitors in the past.
Beaumaris is a symbol of both Edward's conquering achievement and the long Welsh struggle for independence against English rule. The castle evokes memories of medieval battles and sieges through the centuries. While no longer strategically important, Beaumaris has an enduring fascination for visitors as one of the great castles of Wales.
The Last and Greatest Medieval Castle
Beaumaris was the last great fortress Edward I attempted in North Wales. Built from 1295 on Anglesey to command the sea lanes, its concentric design and multiple fortifications would have made it near-impregnable had construction ever been completed.
Although the ambitious scale proved too much to finish, Beaumaris remains a vivid reminder of Edward's iron ring of castles enclosing Wales. After centuries of neglect, it now draws visitors as one of Britain's finest ruined fortresses, and its walls continue to command the Anglesey coastline.
Deepen Your Understanding
→ Harlech Castle: Edward I's cliff-top fortress on Cardigan Bay and the site of the longest medieval siege in British history.
→ Flint Castle: The first of Edward I's Iron Ring, built in 1277 to anchor English control on the Dee Estuary.
→ Ewloe Castle: Llywelyn ap Gruffudd's hidden Welsh fortress in the borderlands of Flintshire, built to resist the very English advance that Beaumaris was designed to complete.
→ Montgomery Castle: The Norman border fortress that guarded the Welsh Marches for five centuries.
