Clegir | ©Si Panton



An intriguing collection of problems dotted around the Brynrefail end of Llyn Padarn and up across the Fachwen hillside. The best lines are quite spread out and are perhaps best appreciated as part of a wandering circuit. Alternatively, the specimen hunter may wish to parachute in to pick off specific problems, such as the super classic Harris’s Arete 6B, which was first climbed by Al Harris in the early 70s. Craig yr Undeb has an interesting history – this is the place that the local quarrymen used to congregate for their union meetings back in the 19th century.


Fachwen, like the nearby Clegir bouldering area, has a major location advantage. Sitting just outside of the rainy mountain zone – it will often be dry and sunny here when the Llanberis Pass is blighted by rain. On cold, windswept days some shelter can be found in the woods at Split Rock.
During the hotter summer months shade can also be sort out here, and on the nearby Craig yr Undeb.


The most obvious and easy access venue here is Craig yr Undeb situated by the old Llanberis road close to the Brynrefail end of Llyn Padarn. Exploration of the hillside above the Fachwen road will lead you to a series of interesting walls and boulders. These do take some finding so unless you can find a willing local to show you around a guidebook is essential.

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Safety & Access

The publisher of this website accepts no responsibility for the way in which readers use the information contained therein. The descriptions and recommendations are for guidance only and must be subject to discriminating judgement by the reader. Advice and training should be sought before utilising any equipment or techniques mentioned within the text or shown in any of the photographic images. Bouldering is an activity with a danger of personal injury or death. Participants in this activity should be aware of and accept these risks and be responsible for their own actions and involvement.


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