Yr WyddfaSnowdon

Yr Wyddfa — Snowdon — is the highest mountain in Wales and England, rising to 1,085 metres (3,560 feet) above sea level. More than 600,000 people reach its summit each year, making it one of the most climbed mountains in the world. Yet for all its popularity, it remains a serious mountain: unpredictable weather, steep ground, and rapidly changing conditions demand respect and proper preparation.

The Six Routes

Six main paths ascend Yr Wyddfa, ranging from the long but gentle Llanberis Path to the adrenaline-soaked knife-edge of Crib Goch. All routes are well-maintained but all require appropriate footwear, clothing, and navigation skills — this is a mountain above the treeline with exposure to Atlantic weather systems.

Hafod Eryri — The Summit

The summit building, Hafod Eryri, opened in 2009, replacing a Victorian structure memorably described by Prince Charles as "the highest slum in Wales." The new building, designed by Ray Hole Architects, is built into the summit plateau and clad in local stone, earning BREEAM "Excellent" sustainability certification. It houses a café, toilets, and a small exhibition about the mountain's geology and wildlife. It is open from late spring to early autumn, conditions permitting. Don't rely on it being open — carry your own food and water.

The Ordnance Survey triangulation pillar at the summit marks the highest point. On a clear day, the views extend to the Wicklow Mountains in Ireland (100km), the Isle of Man, and on exceptional days, as far as Snowdon's name implies: to "snow-dun," the Saxon description of a snow-covered hill visible from the lowlands far to the east.

Snowdon Mountain Railway

The Snowdon Mountain Railway has been running since 1896, making it the only public rack-and-pinion railway in the United Kingdom. The rack-and-pinion system — where a toothed rack rail between the running rails engages with a cogwheel beneath the locomotive — allows the trains to ascend gradients of up to 1 in 5.5 (18%). The journey from Llanberis station to the summit takes approximately 60 minutes and covers 7.6km, ascending 973 metres. Services run from late March to early November, weather permitting. The railway does not always complete to the summit — Clogwyn station (halfway up) is the terminus on windier days. Check the railway's website for current operating status before travelling.

Seven diesel locomotives and four steam locomotives operate the service, carrying up to 450 passengers per hour in peak season. The steam engines — some dating to the 1890s — burn coal and water in an age of electric trains. The railway is a listed structure and a remarkable piece of Victorian engineering.

Geology: An Ancient Volcanic Arc

The rocks of Yr Wyddfa are among the oldest exposed at the surface anywhere in Wales. The summit is capped with Ordovician mudstones formed from sediment deposited on an ancient seafloor around 444 million years ago. Below these lie the volcanic rocks — rhyolites, basalts, and ashes — that accumulated when northwest Wales sat astride a subduction zone, with oceanic crust diving beneath the proto-Welsh landmass and generating volcanic eruptions comparable to the modern Cascades of Oregon.

The dramatic modern landscape is the work of ice. During the Last Glacial Maximum (around 20,000 years ago), Eryri sat beneath a substantial ice sheet. As the ice retreated, glaciers carved the classic cwms — the deep armchair-shaped hollows that now contain lakes like Glaslyn (beneath the summit), Llyn Llydaw (on the Miners' Track), and Cwm Idwal (in the Glyderau). The sharp arêtes — Crib Goch, Crib y Ddysgl — are the ridges left between adjacent cwms, sharpened by freeze-thaw action along their crests.

Mythology

Yr Wyddfa carries layers of Welsh mythology. The mountain's Welsh name means "the great tomb" or "the burial mound" — it is said to be the burial place of the giant Rhita Gawr, who made himself a cloak from the beards of the kings he had defeated. When the legendary King Arthur fought and killed Rhita, he was buried on the mountain's summit.

Arthur himself is said to sleep beneath Yr Wyddfa with his warriors, waiting to return when Wales has need of him. The tradition of the sleeping king, found across Celtic cultures, has particular force here. Glaslyn — the green lake beneath the summit — is said to be the home of the Afanc, a water monster that caused catastrophic floods until it was chained and dragged to the lake by oxen.

When to Go

Yr Wyddfa can be climbed in any month of the year by experienced mountaineers, but conditions vary enormously. June, July, and August offer the longest days and most settled weather — though the mountain is at its most crowded during school holidays. May and September are often ideal: quieter, good daylight, and the heather and bilberry adding colour to the hillsides. April and October bring more volatile weather but potentially spectacular conditions — and dramatically fewer people.

Winter — November to March — requires full winter mountaineering skills. Ice and snow can persist well into April on the north-facing cwms. Crampons and ice axes are not optional in these conditions; they're survival equipment. The Llanberis Mountain Rescue team attends over 100 incidents on Yr Wyddfa each year, a significant proportion of which involve under-equipped visitors.

What to Take

Even in summer, the summit temperature can be 15°C colder than the valley and winds regularly exceed 50mph. Take: waterproof jacket and trousers, warm mid-layer, hat and gloves (even in August), sturdy walking boots with ankle support, OS map and compass (phone GPS fails — take paper backup), sufficient water (at least 2 litres), food for the day, and first aid kit. Tell someone where you're going and when you expect to return.