Tan y Grisiau - The Moelwyns Classic Rock Climbing Venue

Tan y Grisiau - The Moelwyns Classic Rock Climbing Venue

Page Type Page Type: Mountain/Rock
Location Lat/Lon: 52.98653°N / 3.97491°W
Activities Activities: Trad Climbing
Sign the Climber's Log


On the south western boundary of The Snowdonia National Park lies one of the best areas for traditional climbing in the North Wales area. See The Moelwyns

Getting There

By Road
Leave the main A5 trunk road before the Waterloo Bridge at Bettws Y Coed when travelling from the east and take the A470 road through the beautiful Lledr valley past the village of Dolwyddelan. After climbing over a pass and following the downslope past the slate piles from quarrying you will arrive at Blaenau Ffestiniog. Take the road to Tan Y Grisiau and find car parking at the end of the public road. The three cliffs above the road provide the entertainment.
By Rail
It is possible to travel to Tan Y Grisiau by train from Porthmadog on the coast. This is a narrow gauge mountain railway, constructed to haul slate to the docks for shipping. See Festiniog and Welsh Highland Railways.

Red Tape

There is no Red Tape, much of the area is part of the National Park and access is uncontrolled but please respect the natural world, take nothing away except your memories and leave no trace that you were there. Other parts of the area are privately owned (see Ordnance Survey map) but access for climbing and hiking is not normally restricted.


The bunkhouse at the Bryn Tirion Farm campsite
The bunkhouse at the Bryn Tirion Farm campsite
Camping in the Lledr valley
Camping at Dolwyddelan

One of the best campsites in North Wales is close to the area. This is the campsite at Dolwyddelan Castle. Bryn Tirion Farm is a site that is in such a beautiful area that the views from your tent are sensational and if you are travelling light, there is even a bunkhouse.


The rock climbing - Craig Clipiau and access routes to Clogwyn yr Oen and Craig yr Wrysgan

Access Road to Crags
Access Road to Crags
Up to the Tunnel
Up to the Tunnel
Thumbelina - Clogwyn yr Oen
Thumbelina - Severe, a route on Clogwyn yr Oen
The three cliffs seen from the car park run in a north east to south west line, all at a similar elevation. The most northerly cliff Craig Clipiau (see main image) is seen to the right when facing up the hill and is separated from the other two cliffs by a cable runway that used to be for hauling slate down from the upper quarries to the railway station.

Walking up the private road to the left gives access to the other two cliffs Clogwyn yr Oen and Craig yr Wrysgan

Many of the routes in this area are in the lower rock climbing grades, typically from Difficult to Very Severe, as with any traditional climbing area, protection is arranged by the climbers and there are generally no fixed points for belays or abseils.

The rocks on these crags are volcanic in origin and are consistently solid and reliable in the main. As this area is climbed regularly and is also used by mountain training establishments for beginner coaching, there is very little loose rock or vegetation. Of course, whatever vegetation is found during climbing should be left undisturbed. Friction is generally good even in the wet due to the chystaline structures frequently found. Being south facing crags, these three cliffs do not attract much in the way of algae, moss or lichen and never seem too slippery.

Clogwyn yr Oen
The left hand side of Clogwyn yr Oen
Redundant cableway from the slate mine
Redundant cableway from the slate mine

Descent routes from the cliffs are straightforward and can be found in the main guidebooks.

If the cliffs are followed to their tops, an industrial landscape will be revealed, the results of slate quarrying are all around.

An interesting way of descending is to take the route of the old cableway through a tunnel bored in the top of the ridge between Craig Clipiau and Clogwyn yr Oen, Some care is required due to loose slates but the line is very direct as seen in the fotos below.


Clogwyn yr Oen and Craig y Wrysgan

Colin belays on Kirkus Direct
Colin belays at the foot of the crag
The lower slabs of Clogwyn yr Oen
The lower slabs of Clogwyn yr Oen

 Below the cliff, the grassy swards are great for relaxing between climbs and having lunch, they also are handy for lounging about and offering advice to climbing friends when they seem to be struggling on the rock. 

More routes

Moelwyn 5
Andy arranging a runner
Slack a Classic Severe on Craig yr Oen
Slack a Classic Severe on Craig yr Oen
This selection of fotos show the great variety of climbing situations on the three cliffs at Tan Y Grisiau.
Agillivach - severe
Agillivach - severe
Ken on Slick - Severe
Ken on the slabs doing Slick - Severe on Clogwyn yr Oen

White Streak - Hard Severe
Johnnie on White Streak - Hard Severe

At the belay
At the belay


Colin on Grey Slab - Craig Y Wrysgan
Colin under the overhang on Grey Slab, Craig y Wrysgan

Other activities for wet days

Escape from Moria
Escape from the slate mine
On an occasion when the rain is bucketing down and you are soaked through, why not go for a walk underground? The old slate mines have a long tunnel that emerges high up in the Moelwyns. If you are wet anyway there will be no harm done wading through water up to your knees. The tunnel is low overhead but not head-bangingly so. It is not necessary to stoop. 

Good head torches are a must due to the absense of light after a short distance down the tunnel. Side rooms suddenly appear, why not step inside, switch off your headtorches and experience absolute darkness ! Not being able to see anything is a wierd experience, no wonder the Troglodydtes invented fire.

After a long long seemingly endless walk along the decaying submerged rail tracks, in a faint glimmer of light the far exit appears ahead, then the sudden brightness as you get there torments the eyes, but the wind in your face and the fresh air of the walk back to Tan Y Grisiau over the ridges is exhilarating.

Guide books and Map

Climbers Club 2002, Meirionnydd by Martin Crocker, John Sumner, Terry Taylor, Elfyn Jones, with contributions from Mike Rosser, Mike Lewis and Dave Wrennall, ISBN: 9780901601636.

Constable 1982, Rock Climbing in Wales by Ron James,ISBN 978-0-09-464530-1

Grey Stone Books 2005, Scrambles & Easy Climbs in Snowdonia by Jon Sparks, Tom Hutton, Jerry Rawson, ISBN: 1-902017-01-3.

Ordnance Survey, Harlech, Porthmadog & Y Bala, 1:25,000.