After King Edward ‘The Longshanks’ of England conquered North Wales, he was faced with a dilemma, how would he assert dominance over the proud and uprising Welsh people? Well, he did this in the form of creating a small number of strategically placed castles.
All the existing castles west of Chester had been under attack in one way or another by the unrelenting Welsh rebels. This called for the most ambitious and concentrated medieval building project in the entirety of Europe; rebuild all usable castles, and where that is not possible, construct new, modern fortresses.
These formed Edward’s famous ‘Iron Ring’ of Castles.
Harlech Castle
Built on a rocky outcrop closely located to the Irish Sea. This was important for withstanding the Welsh siege of Madog ap Llewelyn. However, this fortification couldn’t hold off the Welsh forever, as Owain Glyndwr captured the great castle 100 years later. It was here where Owain resided and led his rebellion from until it was recaptured by the English in 1409. The castle saw action once more when loyalist forces resisted the parliamentary armies. This world heritage site is classed as one of the finest examples of late 13th-century military architecture.
Caernarfon Castle
Originally the site of a precursor motte-and-bailey castle, until it was replaced with its current stone incarnation. This fortress, and its walled Edwardian town, became the administrative centre of North Wales. Defences were built on a grand scale to secure this key settlement. The castle was briefly captured during the rebellion of Madog ap Llewelyn, but was quickly retaken the following year. As tensions between England and Wales eased, these castles fell into disrepair. Like Harlech, Caernarfon Castle saw renewed use during the English Civil War when it was held by Royalist forces. It has since played host to significant ceremonial occasions, including the investiture of the Prince of Wales. Today, the castle sits within easy reach of scenic walking routes near Caernarfon, making it an ideal historic and recreational destination.
Conwy Castle
The famous castle overlooks the Conwy Estuary as it pours out into the Irish Sea. It withstood the siege of Madog ap Llewelyn, but, like other castles, was later held by those loyal to Owain Glyndwr. Parliament slighted the castle after it was held by Royalist forces during the Civil War. Afterwards, the Earl of Conwy, Edward Conway, stripped the castle of remaining iron. Since then, the castle has remained a ruin – but a picturesque one, famously painted by artists including JMW Turner.
Beaumaris Castle
Beaumaris Castle is the only Iron Ring fortress to be built on the isle of Anglesey. Its strategic importance stemmed from controlling the island, which remained a Welsh stronghold for centuries. The castle’s concentric design and water moat were cutting edge at the time, allowing inner walls to overlook outer defences. Although never completed, its intended grandeur rivals Harlech, and it was built using Anglesey stone quarried nearby.
Costs and Designs
Edward struggled to fund this enormous building programme. While it’s difficult to calculate exact figures, estimates suggest the project cost around £60,000 – the equivalent of approximately £33 million today. These castles were designed by celebrated architect James of St. George, whose designs became more sophisticated with each commission, from the elevated Conwy Castle to the revolutionary concentric plans of Beaumaris.
This reflects just how much effort was required to bring the North Wales area under control!
The well-planned programme, with each borough defended by a formidable castle and each site accessible by sea, firmly established English dominance. Yet in doing so, it left a lasting architectural legacy: an extraordinary concentration of medieval castles in one region. Wales is now regarded internationally as a place of immense historical importance.
From the historic Black Boy Inn, it’s easy to reach all these stunning castles. Many of our guests enjoy combining these historical excursions with local adrenaline attractions and cultural experiences throughout the region. With our central location and centuries-old character, we make an excellent base for those looking to explore North Wales in depth. Discover more about how to find us in Caernarfon or browse our selection of rooms at the Black Boy Inn to plan your next stay.