Caernarfon Castle: Why This Welsh Fortress Mimics the Walls of Constantinople

Caernarfon Castle: Why This Welsh Fortress Mimics the Walls of Constantinople

Caernarfon Castle stands as a brutalist masterpiece of medieval military architecture. Built by Edward I to cement English rule in North Wales, its unique polygonal towers and banded masonry mirrored the walls of Constantinople.

Written by Simon Willliams

Key Facts

  • Location: Caernarfon, Gwynedd, Wales.
  • Built By: King Edward I (construction began in 1283).
  • Architect: James of Saint George.
  • Key Features: Banded masonry, octagonal towers, and the formidable Eagle Tower.
  • Status: UNESCO World Heritage Site and a Grade I listed building.

Caernarfon Castle rears above the confluence of river and strait, its banded walls and polygonal towers a deliberate assertion of imperial might amid the rugged hills of Gwynedd. For more than seven centuries this fortress has stood sentinel, not merely as a military stronghold but as a calculated symbol of conquest and continuity. Built by Edward I in the wake of his final subjugation of Wales, it draws upon Roman precedent, Welsh legend, and Byzantine grandeur to proclaim an authority both ancient and unassailable.

Foundations of Conquest

Work commenced in 1283, scarcely months after Llywelyn ap Gruffudd’s death at Orewin Bridge had shattered native resistance. King Edward I, determined to bind North Wales irrevocably to the English crown, entrusted the design to Master James of St George. The castle supplanted an earlier Norman motte-and-bailey, itself overlying the Roman fort of Segontium. Construction proceeded with ferocious speed: by 1284 the Eagle Tower—grandest of all—was sufficiently advanced to shelter Queen Eleanor during the birth of her son, the future Edward II, on 25 April of that year.

The architecture proclaimed dominion. Polygonal towers, multicoloured banding of stone, evoked the Theodosian Walls of Constantinople, seat of the eastern Roman empire. Edward’s intent was plain: to cast his rule as heir to imperial Rome, legitimised by the Welsh tale of Macsen Wledig’s dream in the Mabinogion—a vision of a fortress beside a river, crowned with golden eagles beside an ivory throne. The Eagle Tower, its three turrets once bearing stone eagles (now weathered), embodied this fusion of myth and propaganda.

Seat of Power and Symbol of Empire

Throughout the later Middle Ages Caernarfon served as administrative heart of the new principality. It housed the justiciar of North Wales, hosted parliaments, and guarded the borough Edward founded alongside it—a planned English town enclosed by walls. Though besieged during Madog ap Llywelyn’s revolt of 1294–95 and Owain Glyndŵr’s rising a century later, it withstood every assault, its defences never breached.

The Eagles: Myth and Meaning

Stone castle with two towers against a clear blue sky

The castle’s most enduring legend centres upon its eagles. Local tradition holds that as long as eagles nest upon the towers, the fortress will endure. This belief, rooted in the carved imperial eagles Edward placed atop the Eagle Tower, drew upon the Macsen legend and Roman symbolism. No resident nesting pairs have ever been documented in historical record; sightings of eagles in the vicinity remain occasional and fleeting. Yet the story persists, a romantic accretion that visitors still seek, gazing skyward for a glimpse of those regal birds as token of the castle’s unyielding strength.

Ghosts and Hauntings

Caernarfon has gathered spectral tales as thick as ivy. The most persistent concerns Queen Eleanor, who died not here but at Harby in Nottinghamshire in 1290, far from Gwynedd. No credible evidence places her death at Caernarfon, nor supports sightings of her phantom drifting through the King’s Gate. Such apparitions belong to folklore rather than fact—embellishments born of the castle’s brooding atmosphere.

A black-armoured knight is said to patrol the battlements by night, perhaps the shade of a long-forgotten sentinel. Disembodied wails and moans echo through the empty wards, attributed by some to restless spirits, by others to the wind keening through arrow-slits and machicolations. Secret tunnels are whispered of beneath the walls, though none have been found beyond the known water gate and postern.

These spectral yarns, while captivating, remain unsubstantiated. They enhance the castle’s aura of mystery, yet its true power lies in stone and history, not in shadows.

Enduring Majesty

Today, a UNESCO World Heritage Site under Cadw’s care, Caernarfon remains one of Britain’s most complete medieval fortresses. Its halls once rang with royal ceremony; now they host visitors drawn by the same imperial ambition that raised them. To walk the battlements is to tread where Edward sought to rewrite Welsh destiny, where legend and conquest entwine.

The eagles may no longer perch in stone, the ghosts may be mere fancy, yet the castle endures—towering, banded, defiant—a monument to one king’s vision and the enduring fascination of our medieval past. Standing upon the banks of the River Seiont, with the Menai Strait beyond, Caernarfon proclaims still the unyielding grip of history upon the land.

Frequently Asked Questions

Why is Caernarfon Castle different from other Edwardian castles?

Unlike the round towers of Conwy or Harlech, Caernarfon features polygonal towers and stripes of coloured stone. This design was a deliberate attempt to mimic the Theodosian Walls of Constantinople, linking Edward I's conquest to the prestige of the Roman Empire.

What is the connection between the castle and the Prince of Wales?

Edward I’s son, the future Edward II, was born at the castle in 1284. According to legend, Edward I presented his newborn to the Welsh people as a prince who "could speak no English." In 1969, it served as the setting for the investiture of King Charles III as Prince of Wales.

Is Caernarfon Castle a concentric castle?

Strictly speaking, no. While it is immensely strong, its design is dictated by the narrow rocky peninsula it sits upon. It lacks the "walls-within-walls" layout of Beaumaris, relying instead on its massive external curtains and integrated town walls for defence.

Deepen Your Understanding

History rarely happens in isolation. The people, places, and events on this page are part of a much bigger story. The articles below explore the threads that connect to what you have just read — follow whichever pulls at your curiosity.

→  Caernarfon Castle: The Imperial Fortress  —  The history and architecture behind the symbolism

→  Why Was Caernarfon Castle Built?  —  Edward I's original strategic vision for the site

→  The Welsh Dragon: History of Y Ddraig Goch  —  The symbol of Welsh identity that Caernarfon was built to suppress — and that endured

→  Owain Glyndŵr: The Last Prince of Wales  —  The rebel who challenged the English authority Caernarfon represented

About the Author

Simon A. Williams

Simon A. Williams

Published Author and Editor-in-Chief · Verified Research

Simon A. Williams is the founder and Editor-in-Chief of Histories and Castles and a published author specialising in medieval British history, early modern legal history, and Celtic folklore. Raised in North Wales within sight of Edward I's Iron Ring fortresses including Rhuddlan, Conwy, Flint, and Caernarfon, his historical work is anchored by direct field research and the analysis of institutional primary records.

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