The Biggest Castle in Wales? It’s This.

Wales has more castles for every square mile than any other European country. The Normans and the English built castles to project their power and to create a base from where they could mount their bids to conquer Wales. Wales is a castle lover’s paradise, but which castle is the biggest?

Caerphilly Castle is the biggest castle in Wales (source). It is also the second largest castle in Britain, behind only Windsor. This formidable fortress covers 30 acres and is surrounded by water. Overlooking the South Wales town of Caerphilly, the castle has a wonderfully domineering presence.

There are over 600 castles dotted around Wales. Varying in style and structure, Caerphilly wins the bragging rights for the largest. In this article, I shall look at:

  • The main features of Caerphilly Castle
  • Why Caerphilly Castle was built
  • The history of Caerphilly Castle
  • What the modern-day visitor can expect
Caerphilly Castle, Wales, surrounded by water
The imposing Caerphilly Castle spans 30 acres, and overlooks the Welsh town of Caerphilly

How Big Is Caerphilly Castle?

Big, is the simple answer. This majestic castle occupies 30 acres of land or 120,000 square meters.

Work began on Caerphilly Castle in 1268, with extensions added during the following years.

At the time it was built, Caerphilly was at the forefront of castle design. Caerphilly Castle was constructed using Pennant sandstone. It was one of the first castles in Britain built with a concentric design, with two inner and two outer wards. The curtain walls meant attacking armies had further obstacles to overcome if they penetrated the outer wall.

The inner wall was also higher than the outer wall. This allowed archers to shoot over the heads of their fellow defenders at any attacking force, In places, the walls were over a foot thick.

The castle consisted of eight towers of various sizes, two gatehouses, and a single drawbridge.

This castle needed to withstand an attack and a siege. It also needed to be a base from where power could be disseminated and the administrative function of the local area carried out. However, access to the castle needed to be withdrawn swiftly and efficiently when required.

This is where another defensive feature sets Caerphilly Castle apart from other castles of the time. The outer walls of the castle were surrounded by a moat, while the inner walls sat on an island surrounded by lakes. These water features had to be negotiated first before any attempt could be made on the inner castle walls by an aggressor.

Caerphilly was one of the first castles designed with such defensive water features. Further bonuses of the water defenses were in protecting the castle defenders from tunneling and the use of siege engines.

The Normans in Wales

After the Norman conquest of England in 1066, their attention turned to Wales. With them came a surge of castle building. Early castles were motte and bailey affairs, involving a wooden tower built high up on a mound of earth.

By the thirteenth century, stone fortifications had made castles far more imposing structures. Much of Wales was by now under Anglo-Norman control, although most of the barons were of Norman descent. However, a local rebellion was never far away.

Back in England, King Henry III was at loggerheads with his barons. This took up his full attention, presenting an opportunity to Welsh leaders to try and wrestle back control of Wales.

One of these leaders was Llywelyn ap Gruffydd. He proclaimed himself Prince of Wales and allied himself with the English king’s baronial opposition. He wanted to expand his power base in Glamorgan. This pitted him against the Anglo-Norman Earls of Gloucester who had similar ambitions for this part of Wales.

Gilbert de Clare

By 1268, Gilbert de Clare was the seventh Earl of Gloucester. He also held the title of Lord of Glamorgan and was one of the most powerful of the Welsh Marcher lords. Gilbert de Clare was increasingly concerned about the threat from Llywelyn ap Gruffydd. He decided he needed a castle to help defend the lands he had won.

He not only wanted a castle, but he also wanted it built in rapid time.

Work on Caerphilly Castle began in 1268 at the site of an old Roman fort. The cost of the building work must have been astronomical. Huge defensive walls and imposing towers were constructed over the next three years, although not without some interference from de Clare’s arch-nemesis.

Llywelyn ap Gruffydd orchestrated raids on the castle. One of these in 1270 saw the raiders burn some of the unfinished buildings as well as stored materials. However, de Clare was not to be put off his dream castle. Work resumed in 1271 and soon the perimeter walls, curtain walls, towers, and the Great Hall were complete. Caerphilly Castle was taking on its imposing form.

History of Caerphilly Castle

Llywelyn ap Gruffydd was killed in battle in 1282. His decapitated head was sent back to London and displayed on the gatehouse at the Tower of London. However, Gilbert de Clare could not rest easy following the demise of the Prince of Wales.

The second phase of building was completed around 1290. Four years later, a Welsh rebellion by Madog ap Llywelyn saw Caerphilly Castle under threat. The castle’s fortifications proved their worth, and the castle held firm. Unfortunately, the same could not be said for the town, which was burned.

In 1295 Gilbert de Clare died. Caerphilly Castle stood as his impregnable castle.

However, as Edward I advanced north through Wales, Caerphilly became further from the front line of the hostilities. The need for Caerphilly Castle as a fortress receded, and its future occupiers saw its potential as a palatial home instead.

The biggest castle in Wales - Caerphilly Castle
Caerphilly Castle has endured sieges, battles, an uprising, and has harbored King Edward II

Refuge to Edward II

Caerphilly has been the residence of famous historical names across the centuries.

In 1306, Hugh Despenser, a favorite of King Edward II, married Eleanor de Clare. His wife was the daughter of Gilbert de Clare, and she inherited Caerphilly Castle in 1317.

Hugh Despenser set about turning the castle into a palatial palace befitting his perceived status. This included the enlargement and ornate refurbishment of the Great Hall. The hall was now a suitable centerpiece for such a noble family, one where great feasts could be held.

While Hugh Despenser was a favorite with the King, who bestowed him with titles, he was less than popular with the Queen and much of the court nobility.

When Queen Isabella joined forces with Roger Mortimer in 1326 to rid the King of the influence of the Despensers, support for Edward soon disappeared. The King fled to Wales to join Hugh Despenser at Caerphilly Castle.

The pair eventually fled the castle before being captured by the Queen’s forces. The King was deposed and replaced by his son, Edward III. The king’s favorite, Hugh Despenser, was executed by hanging, drawing, and quartering.

Caerphilly Castle was besieged, with the siege ending in March 1327 after an agreement was struck with the remaining defenders.

Left to Fall into Disrepair

Following the saga with King Edward II and Hugh Despenser, Caerphilly Castle once again became a palatial home for nobility. The castle became a residence of the Earls of Warwick through marriage. Money was once again poured into the castle to make it the primary residence in the area.

Another famous name from history to take control of Caerphilly Castle was Jasper Tudor, Earl of Pembroke. Jasper Tudor was a loyal guardian of his nephew, the future King Henry VII. His loyalty was rewarded with the Lordship of Glamorgan. He was also made constable of several castles in Wales, with Caerphilly passing to him in 1486.

However, it was around this time that the importance of Caerphilly Castle began to wane, and it started to fall into disrepair. By the start of the 16th century, the neglected castle was more a ruin than a stronghold. The defensive lake system was now just a swamp. Stone from the walls was stolen, and by the 18th century, the great towers were in a state of collapse.

The following table offers a timeline showing the castle’s principal custodians and events in Medieval times.

1268Gilbert de Clare starts building Caerphilly Castle
1270Castle attacked and damaged during construction by Llywelyn ap Gruffydd
1271Main building work completed
1294Castle attacked during an uprising led by Madog ap Llywelyn
1307Inherited by Eleanor de Clare, wife of Hugh Despenser
1326Edward II takes refuge
1327Siege of the castle ends
1416Richard Beauchamp, Earl of Worcester becomes custodian
1449Richard Neville, Earl of Warwick takes ownership
1486Jasper Tudor, Earl of Pembroke takes control of Castle

A Time for Restoration

The first stage of restoring this magnificent structure came at the latter end of the 18th century. The Marquis of Bute, John Stuart, took possession of Caerphilly Castle in 1776. You can only imagine his thoughts as he surveyed the walls of a castle so long in decline.

The castle renovation became a family labor of love. This was no quick fix, but a long-term project. John Crichton-Stuart, his great-grandson, brought the Great Hall back to life toward the end of the 19th century. The next generations continued the good work, carrying out extensive renovations.

Towers were rebuilt and the lakes re-flooded. Caerphilly Castle was gradually resembling its former glorious self. Further restoration work begun in 1928 was bold and against the thinking of the day. The general mood of the time was conservation, not reconstruction.

In 1950, after generations of hard work and expense, the Stuart family donated the keys to Caerphilly Castle to the state. It is now managed by the Welsh heritage agency, Cadw.

Visiting Caerphilly Castle Today

Today, visitors to Caerphilly Castle can explore the 30 acres of grounds, walk around the lake that once formed its defensive feature, and enjoy the views of the surrounding countryside. Castles like Caerphilly, even with structures still in partial ruin, retain an atmospheric pull.

The castle is accessed over the drawbridge. From here you can explore the grounds and the surviving towers. If you climb the Gatehouse Tower, you are rewarded with stunning views over the castle grounds.

The Great Hall is a highlight of the castle and still functions today, holding Medieval banquets. There is plenty of information to learn about the castle and its history as you go around, including exhibitions. Displays include siege weapons, while the staterooms also offer a glimpse back into the past.

A quirky feature of the modern Caerphilly Castle which draws people to the site is its leaning tower. The southeast tower is said to lean by 10 degrees, making it one of the most lop-sided structures in the world.

There is a degree of uncertainty about how the tower became so wonky. Local folklore says it was caused by gunpowder during the English Civil War. However, it is possible that stones taken from the tower by locals for other use while the castle was neglected could be the reason.

The following video guides you around the modern-day Caerphilly Castle.

Visitors can expect an even more enhanced experience soon. In 2021, an investment of £5 million was announced by Cadw, aimed at turning Caerphilly Castle into a major tourist attraction (source). The improved customer experience will feature improvements within the Great Hall to help return it to its medieval splendor. Conservation, improved accessibility, and facilities, plus a new visitor center are also key elements of the investment.

You May Have Already Visited Virtually

You may have viewed the grounds of Caerphilly Castle without realizing it. The castle has been the location for several TV shows and films.

Caerphilly Castle was chosen to film scenes for an episode of Doctor Who, Robot of Sherwood, when Peter Capaldi was in the titular role. This was not the first time the castle had featured in Doctor Who, having been used a couple of times in earlier series.

The acclaimed drama Wolf Hall, based on the Hilary Mantel novel, also shot scenes at Caerphilly Castle, as did the popular fantasy show Merlin, which ran for five seasons.

Further filming to take place at Caerphilly Castle includes Restoration, Gawain, and the Green Knight, Sword of the Valiant, and Galavant. Therefore, Caerphilly Castle is a location sought out by film and TV fans wanting a glimpse of where their favorite shows and films were made. It was noted how visitor numbers went up after Merlin was aired featuring Caerphilly Castle.