Caernarfon Castle

Caernarfon Castle Was Built to Make a Point About Who Won

King Edward I of England began constructing Caernarfon Castle in 1283, immediately after his conquest of Wales. It was not just a military installation. The design’s distinctive banded stonework – alternating layers of different-coloured limestone – was a deliberate reference to the walls of Constantinople, signalling to a defeated Welsh population that their new English ruler was playing in a different historical league. The walled English-only town attached to the castle explicitly barred Welsh people from living within its walls. Knowing this history does not diminish the architectural achievement – the castle is genuinely extraordinary – but it reframes the experience of walking its walls from a pleasant heritage outing into something with actual moral weight.

Caernarfon is now a UNESCO World Heritage Site, jointly listed with Harlech, Conwy, and Beaumaris as the Castles and Town Walls of King Edward in Gwynedd. Together they constitute one of the most coherent examples of medieval military architecture in Europe, all built within a decade as part of Edward’s deliberate encirclement of Welsh independence.

The Architecture

Where Harlech and Beaumaris are concentric-plan castles – concentric rings of walls giving defenders multiple defensive lines – Caernarfon uses an angular, irregular plan following the natural contours of the site at the mouth of the River Seiont where it meets the Menai Strait. The walls reach 3.4 metres thick in places. The castle could be supplied by sea even when the land approaches were cut off, which made it functionally impregnable for 14th-century siege technology.

The Eagle Tower at the western end is the most distinctive structure: three tiers of turrets on its summit, a bronze eagle at the very top, and arrow slits cut at angles to cover multiple directions simultaneously. The tower housed the castle constable and is the best-preserved of the major towers. The walls walk – the main visitor experience – takes you along the parapet circuit with views over the town, the harbour, the Menai Strait toward Anglesey, and on clear days the mountains of Snowdonia. The Eagle Tower gives the highest vantage point.

Cadw (the Welsh Government’s Historic Environment Service) manages the castle. Admission is around 12 pounds for adults. Allow 2-3 hours to do the walls properly.

The Town

The medieval town walls, part of the same UNESCO designation, still substantially surround the historic centre. Caernarfon today is a working Welsh market town with a strong Welsh-language character – Gwynedd is one of the most Welsh-speaking areas in Wales, with around 70% of the population using the language daily. Hearing Welsh on the street and in shops is the norm here in a way that is not true in Cardiff or Swansea. That alone makes the town feel like a different country from the one that built the castle to control it.

The harbour on the Seiont is pleasant with a few cafes and pubs. The Black Boy Inn on Northgate Street, a 16th-century pub with low beams and a good selection of Welsh ales, is the most historically interesting eating and drinking option in town.

Snowdonia Access

Caernarfon sits at the western edge of Snowdonia National Park, making it a natural base for the mountain. The Snowdon Mountain Railway departs from Llanberis, 12 kilometres southeast, and runs a rack-and-pinion cog railway to the summit – opened in 1896, still running, and the easiest way to reach the top of Wales without hiking. The summit has a cafe at 1,085 metres.

For walkers, the Llanberis Path is the most-used route to Snowdon’s summit (about 9 kilometres return, 5-6 hours). It does not require technical skill but the upper section is long and exposed and carries heavy summer crowds. The Pyg Track and Miners’ Track from the Pen-y-Pass car park are better options for experienced walkers who want more varied terrain and somewhat fewer people.

The Dinorwig Power Station inside Elidir Fawr mountain near Llanberis is one of the more surprising visitor experiences in Wales – a pumped-storage hydroelectric scheme carved inside a mountain, with caverns large enough to hold the Palace of Westminster. The visitor centre has tours. It is genuinely remarkable engineering and almost nobody outside Wales knows it exists.

Getting There

Caernarfon has no train station. The nearest rail connection is Bangor, 15 kilometres east, with regular buses onward. By road the town is on the A487, about 1.5 hours from Chester. Parking near the castle is limited; the Slate Quay car park is 5 minutes’ walk from the entrance.