The first thing you see in Caernarfon is the castle, and it is meant to be. Edward I began building it in 1283 after conquering the Welsh princes, and he designed it to impress as well as to defend, with polygonal towers and bands of different coloured stone in imitation of the walls of Constantinople. It was the seat of English power in north Wales, and in 1284 Edward's son, later Edward II, was born here and became the first English Prince of Wales, a title since given to the heir to the throne. The castle, along with Conwy, Harlech and Beaumaris, is a UNESCO World Heritage Site, and the sheer scale of it, rising above the Menai Strait, is staggering.
But Caernarfon is not simply a museum. It is a living Welsh town of nearly ten thousand people, where Welsh is spoken in the shops and cafés as the first language, and the atmosphere is friendly and unpretentious. The old town inside the walls has narrow lanes, pubs and small shops, and the quay on the Seiont is a pleasant place to sit. Fuel, supermarkets and anything else you need are easy to find, and the town makes a good base for exploring Snowdonia. A narrow-gauge railway, the Welsh Highland, runs from here to Porthmadog through the mountains.
The ride from Caernarfon through the Llanberis Pass is among the best in Wales. The road runs southeast along the shore of Llyn Padarn, past the old slate quarries at Llanberis, whose huge terraced steps mark the mountain across the lake, and then climbs into the pass itself, a steep-sided glacial valley with a river and walls of boulders. Snowdon, at 1,085 metres the highest peak in Wales, rises to one side. The road narrows as it climbs to Pen-y-Pass, with tight bends and rock on both sides, and it is spectacular, but it can be crowded with walkers, cyclists and cars in summer.
The weather in Snowdonia is changeable and often wet, with low cloud and sudden showers even in July, so wet-weather gear is essential. The surface can be greasy, and sheep wander across the road without warning. Early morning is the best time, when the light is clear and the traffic is thin. Have a good breakfast before you leave, and keep an eye on the clouds.