Restricted Access

July 2018 - Major rockfall affects Lost World/Mordor areas. In recent years there have been significant and massive rockfalls (hundreds if not thousands of tons of rock)  in this area, and in early July another significant rockfall occured here, that would have wiped out anyone in this area at the time. There is further significant and unpredictable rockfall likley here and it would be prudent to avoid this area. 

The Upper Dinorwig quarries are mainly owned by First Hydro. Access for climbing or any access away from the designated footpaths is not permitted by the landowners, due to liability concerns. However it's rare for climbers to be asked to leave and in general it appears that if climbers keep a low profile, avoid damaging fences, do not interfere with any of the power station buildings or apparatus or any of the historic structures within the quarry that climbing is possible. Access to the whole of the upper quarries have become especially sensitive in recent years and climbers should not gather in large numbers, especially at Dali's Hole area. Bolts have been removed from Dali's Hole by a local climber (late 2010) who was concerned that continued use of this venue by large groups of climbers would jeopardise access to the whole site. There have also been a number of reported altercations between climbers and First Hydro security staff over the years at this venue.

BMC advice remains unchanged - the landowners do not give permission for public access (including for climbing) away from the public paths. Please do not damage fences or signs and if accosted by security staff, please be courteous and report any issues to the BMC.

Seasonal Restrictions

Reason: Nesting Birds

A fence has been errected across the base of the Dali's Hole area to deter access to this area due to liability concerns by First Hydro. Access to this area is especially sensitive at this time and security staff have been reported to be asking climbers to leave this area.

75m, 2 pitches.

Rockfax Description
A great two-pitch expedition up the full height of the wall. The first pitch is enough for many. Start below a bolted slanting groove.
1) 6b, 25m. (a.k.a. The Wobbly Ladder Pitch) Climb up the groove heading for the hanging ladder. From a good foothold, jump for the ladder or make a traverse across on bore-holes. Scamper up the ladder to a bolt belay by the tunnel.
2) 7a, 50m. A beast of a pitch. Head up towards the wavy groove capped by a square block. Some traditional thrutching up this leads to easier ground and the base of a square-cut groove. This proves trickier than it appears. Belay on a bolt/thread on the viewing platform above. © Rockfax

UKC Logbook Description
An entertaining 2 pitch slate adventure from the very bottom of the ‘Twll Mawr’ hole topping out on the viewing platform adjacent to the track.
The route can be accessed through the Twll Mawr / Peregrine Wall Tunnels and walking down the scree slope to the bottom of the hole, or alternatively a multiple abseil if you have a spare rope. Start just left of ‘In the Line of Fire’ (left of Supermassive Black Hole) by an obvious and well bolted slanting groove below the hanging ladder.
Pitch 1 -25m (6b) ‘The Wobbly Ladder Pitch’ - climb the bolted series of grooves to gain a small ledge on the main face level with the bottom of the hanging ladder. From a good foothold it is possible to launch / dyno / fly / fall rightwards to gain the ladder – a unique and fun move! The faint hearted i.e. those refusing to fly can gain the same point by traversing along a series of bore holes. Run up the ladder via 2 bolts to a bolt belay by the tunnel.
Pitch 2 – 50m (7a) ‘the big pitch’ - head up towards the incredibly smooth wavy groove capped by a huge square chock stone (solid). Squirm up the frictionless groove and if successful carry on up over easier ground to gain the bottom of a square cut groove. The final groove proves trickier than it looks; bolt / thread belay on the viewing platform above.

Both pitches can be climbed separately due to the easily accessible bolt belay by the tunnel, which allows you to walk in or out if you’re not doing both pitches.

NOTE: If you've enjoyed any of the bolted routes in Twll Mawr please consider donating to the North Wales Bolt Fund :-)

FA Ian Lloyd-Jones and Sion McGuinness (Pitch 1) 25/Nov/2011.


Dinorwic Slate - Multi Pitch Sport Climbs , All the Llanberis SLATE sport @ 7a & 7a+ , Slate Sport , Rarely repeated Slate Sport 7's , Twll Mawr Big Wall 1000 Metre Challenge! , Sl@teheads Sl@te , Slate Mastery , All multi-pitch sport routes (England and Wales) , North Wales To Do List


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High 7a+
Mid 7a+
Low 7a+
High 7a
Mid 7a
Low 7a
High 6c+
Mid 6c+
Low 6c+
Votes cast 5
Votes cast 6
Style of Ascent
Alt Leads
Not Set
Ground Up
Not Set
Route of Interest
Choose Life

Grade: 7a ***
(Bryn Eglwys Quarry)

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