The Diagonal

Page Type Page Type: Route
Location Lat/Lon: 52.64290°N / 4.00926°W
Additional Information Route Type: Trad Climbing
Seasons Season: Spring, Summer, Fall, Winter
Additional Information Time Required: Less than two hours
Additional Information Difficulty: Severe (USA 5.5 - 5.7)
Additional Information Number of Pitches: 2
Sign the Climber's Log


The aptly named The Diagonal (Severe) takes an obvious line up a large diagonal crack, which slants up right from the base of The Diamond Wall to the top of The Bastion Face. The route is short but atmospheric, and although it might not be the greatest route on Craig yr Aderyn, it takes place on some of the crag’s cleanest, soundest rock, and is an excellent starting point for anyone climbing there. The 37 metre route is usually climbed in two pitches, however it can be split into three by belaying on a ledge around 10 metres below the usual belay point. This allows the climbers involved to communicate more easily, as since the route was first climbed, a tree has grown around the usual belay point, obscuring the climbers' view of one another and muffling their calls.

FA: A. Howard and D. Davies (Alternate Leads), November 22nd 1964.

Getting There

Craig yr AderynThe route follows the large diagonally rising fissure below the Diamond Face (Photo by Nanuls)
The Diagonal (Severe)Halfway along the route near the first ledge, it is possible to belay here if you wish (Photo by Nanuls)
Craig yr AderynThe Diagonal ends above the Dysynni Valley and looks out towards Cardigan Bay some five miles to the west (Photo by Nanuls)
Bastion DescentThe descent ramp which runs down the back of the Diamond Face and is the quickest way back to the base of the rock (Photo by Nanuls)

Most visitors to Craig yr Aderyn will approach the rock from the east, if you have to approach from the west, then you clearly know the area well enough already, and therefore don’t need a section such as this to help you get there. So, if you are coming from the east, you need to turn off the A470 at the Cross Foxes Inn junction (SH 766 167), and drive south along the A487 for some 6km to the junction for the B4405 near the Minffordd Hotel (SH 732 114). For those familiar with the area, this is the same turning as you would take for the car park on the southern side of Cadair Idris where the Minffordd Path starts. Drive along the B4405 as far as Abergynolwyn (SH 677 069). In the centre of the village there is a crossroads, turn right here and drive north up a narrow unclassified road to another set of crossroads marked by a public phone box (SH 662 079). Turn left here and drive west along another unclassified road. After a around a kilometre and a half the road reaches Craig yr Aderyn and passes along the base of its north face, There are various lay-bys along the road where parking is available, the best ones for this route are located just beyond the junction at grid reference SH 643 071. The start is at the bottom of the obvious crack that the route ascends.

Route Description

Pitch 1 (26m): Take a line just below the crack to a small ledge, the first 9m of climbing is poorly protected so take care. There’s a friend jammed in a crack on the left side of the ledge. You can belay here if necessary. Climb more in the crack to an awkward final move and another ledge where you can build a boulder and tree belay. The final moves can be a bit vegetated, particularly in summer.

Pitch 2 (11m): Move easily right over some protruding boulders and a stance on the buttress then climb to the top via a clean cut groove on the left.

Descend via a narrow ramp which can be accessed by walking a little further uphill and slightly to the left.

The Diagonal Route. For a clean version of the photo click HERE

Essential Gear

A single 50 or 60m rope will be fine (you may want to use a double or twin but its not essential) a moderate rack of nuts, hexes and maybe a few cams. Also be sure to carry a selection of slings and screwgates for constructing belays. The route is best done in rock shoes as boots would be way too cumbersome. Naturally you will also need all the other paraphernalia associated with climbing and hill walking in Wales: full waterproofs, fleece, hat, gloves and of course some lunch.


Open Space Web-Map builder Code
Navigation Maps

Ordnance Survey 1:25k Explorer Series OL 23 Cadair Idris & Bala Lake/Llyn Tegid

Ordnance Survey 1:50k Landranger Series 124 Porthmadog & Dolgellau

Harvey Map Services 1:25k Snowdonia Cadiar Idris

Harvey Map Services/BMC 1:40k British Mountain Map Snowdonia South

Road Maps

Ordnance Surbey Tour Series North and Mid Wales


Snowdonia (Official National Park Guide) Snowdonia (Official National Park Guide) by Merfyn Williams with contributions from Ian Mercer and Jeremy Moore

A handy book full of useful information and interesting facts about the National Park.
Climbers Club Guide Wales: Meirionnydd Climbers' Club Guide Wales: Meirionnydd by Martin Crocker, John Sumner, Terry Taylor, Elfyn Jones, with contributions from Mike Rosser, Mike Lewis and Dave Wrennall

The definitive climbing guide to the area. Contains detailed descriptions and excellent diagrams of all known routes on Craig yr Aderyn. An essential purchase if you plan to do a lot of climbing in Mid Wales.

External Links

The BastionThe Bastion - The Diagonal follows the large crack below the Diamond Face (Photo by Nanuls)
Craig yr AderynCraig yr Aderyn from Castell y Bere (Photo by Nanuls)

Government Bodies and Official Organisations

Snowdonia National Park Authority

Council for National Parks

Association of National Park Authorities

Natural Resources Wales


Royal Commission on Ancient & Historical Monuments in Wales

Gwynedd Archaeological Trust

Snowdonia Society

The National Trust

Hiking, Climbing and Mountaineering Organisations and Companies

British Mountaineering Council

The Climbers’ Club


Plas y Brenin National Mountain Centre

Hightreck Snowdonia


Mountain Weather Wales

Weather from the Met Office

BBC Weather

Tourist Information

Visit Wales

North Wales Tourism Partnership

Local Information from

Local Information from Snowdonia Wales Net

North Wales Index


Welsh Public Transport Information

UK Train Timetable


Youth Hostel Association in Wales

Pete's Eats

Pen-y-Gwryd Hotel

Maps and Guidebooks

Ordnance Survey

Harvey Map Services

Cicerone Guidebooks

Climbers’ Club Guidebooks


North Wales Bouldering

Cordee Travel and Adventure Sports Bookshop

Wildlife and Conservation

Joint Nature Conservation Committee

Natur Gwynedd

North Wales Wildlife Trust

Royal Society for the Protection of Birds



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