Safety information
Welsh mountains demand respect. Conditions can change in minutes — even Snowdon in July sees casualties from inadequate kit and unexpected weather.
Carry: waterproofs, walking boots, warm layer, hat & gloves, OS Explorer OL17 (Snowdonia) or OL18 (Harlech & Bala), 1.5 L water, charged phone, head torch. Check the weather at mwis.org.uk on the morning. In an emergency call 999, ask for Police / Mountain Rescue, give your what3words location. Local team: the relevant Mountain Rescue Team.
At a glance
The higher Glyders summit (999 m / 3,278 ft) — chaotic angular rock formations across the summit plateau, the Cantilever Stone on adjacent Glyder Fach (15 min), and views of Snowdon across the Llanberis Pass. Classic routes via Devil's Kitchen from Ogwen or Pen-y-Pass. No summit facilities; navigation skills essential. Serious mountain. LL55 4UB.
About Glyder Fawr
Glyder Fawr (999 m / 3,278 ft) is the higher of the two main Glyders summits and one of the most visually extraordinary mountains in Snowdonia. The summit plateau is covered in a dense field of angular, upright rock slabs — the result of intense frost-shattering of the volcanic bedrock during and after the last Ice Age — giving the mountain a landscape unlike anything on Snowdon or the Carneddau. This is wild, chaotic, elemental terrain: rock sticking up at all angles, boulders balanced on their neighbours, pinnacles of splintered stone in every direction.
Glyder Fach (994 m, 15–20 minutes from Glyder Fawr across the summit plateau) has the famous Cantilever Stone — a flat slab horizontally balanced on vertical rock fins, one of Snowdonia's great photographic landmarks. The combination of the two Glyders summits, typically done together with Tryfan (the great rocky pyramid that defines the Ogwen Valley), constitutes one of the finest mountain days in Wales.
The main approaches are the Devil's Kitchen (Twll Du) route from Ogwen (steep, dramatic, highly recommended) and the traverse from Pen-y-Pass. The Snowdon Sherpa bus serves both Pen-y-Pass and Ogwen in summer. The mountains are in the heart of Snowdonia, 5 miles from Llanberis and 3 miles from the Ogwen car park (LL57 3LZ).
Find it on the map
Frequently asked questions
Glyder Fawr is notable for the chaotic rock architecture of its summit plateau — an extraordinary landscape of angular, splintered rock that looks as if the mountain has been shattered from within. The summit area is littered with upright slabs, balanced boulders, and pinnacles in a density and variety unusual even in Snowdonia's generally rocky landscape. This is the result of intense frost action during and after the last Ice Age: repeated freeze-thaw cycles splintered the volcanic rock into the angular debris that now covers the summit. The nearby summit of Glyder Fach (994 m, reached in 15–20 minutes from Glyder Fawr) has the famous Cantilever Stone — a huge flat slab balanced on vertical fins of rock that appears to defy gravity and has been photographed by climbers and walkers for over a century. The combination of Glyder Fawr and Glyder Fach gives one of the most visually dramatic summit experiences in Snowdonia.
There are three principal approaches to Glyder Fawr. From Ogwen (Llyn Ogwen car park), the Devil's Kitchen (Twll Du) route ascends steeply through a rocky ravine to Llyn y Cwn (the summit lake below the main ridge) and then to the summit — approximately 3.5 miles and 900 metres of ascent. From Pen-y-Pass, the Pyg Track or Miners' Track can be combined with an ascent of the Glyderau for a full Glyders traverse — a long, serious day. From Llanberis, the approach via the Llanberis Pass climbs to Pen-y-Pass and then onto the ridge — the longest approach but avoiding the crowded car park at Pen-y-Pass in summer. The Glyders traverse (Tryfan → Glyder Fach → Glyder Fawr, descending via Devil's Kitchen to Ogwen) is one of the classic mountain days in Snowdonia — approximately 8–10 miles with 1,200 metres of ascent, suitable for experienced mountain walkers only.
The Cantilever Stone is a large flat slab of rock on the summit plateau of Glyder Fach (adjacent to Glyder Fawr) that appears to be balanced horizontally on vertical columns of rock — a natural geological formation created by differential erosion of the volcanic strata. The stone has been a landmark and a famous photograph subject since Victorian mountaineers first described the Glyders in print; countless photographs show walkers and climbers balanced on its far end over the apparent drop. The stone is genuinely balanced (or appears so — it is actually partly supported by the rock beneath it) and is safe to stand on, though care is required at the edge. Finding the Cantilever Stone involves some route-finding on the Glyder Fach summit plateau; it is worth locating specifically rather than assuming it will be immediately obvious.
Llyn y Cwn ("Lake of the Dogs") is a small mountain lake on the high plateau between Glyder Fawr and Y Garn — at approximately 780 metres, one of the highest lakes in Snowdonia. It sits in a shallow depression on the plateau above the head of the Ogwen Valley and is passed on the Devil's Kitchen route from Ogwen to Glyder Fawr. The lake has a wild, exposed character in poor weather and a strikingly peaceful quality in good conditions — a high plateau lake with views to the Carneddau. The name may derive from a legend or from the observation that hounds were used in hunting on the high ground. Llyn y Cwn is also the starting point for the descent of Y Garn (947 m) — a technically straightforward descent on steep grass that forms an alternative circuit back to Ogwen.
Glyder Fawr and Snowdon are both serious mountains but have quite different characters. Snowdon is the highest (1,085 m, compared to Glyder Fawr's 999 m), more visited, and has the Snowdon Mountain Railway giving access to the summit café — on summer days, the Snowdon summit can have several hundred people. The paths to Snowdon (Llanberis Path, Pyg Track, Miners' Track) are well-maintained and well-signed. Glyder Fawr has no railway, no summit café, no signage on the summit plateau, and significantly fewer visitors than Snowdon. The summit terrain (chaotic rock) is more technically demanding than any Snowdon path except Crib Goch. The views from Glyder Fawr include Snowdon directly across the Llanberis Pass, giving a distinctive perspective on the highest Welsh mountain that cannot be obtained from Snowdon itself. For experienced walkers, the Glyderau offer a quality of mountain experience closer to the Alps (in miniature) than anything on the Snowdon routes.