Carneddau Excursion (Cwm Eigiau loop)

A glorious circular route in the Carneddau, from the remote parking near Llyn Eigiau (SH732663).
A Snowdonia walk for the more adventurous, taking in less walked peaks and an enjoyable ridge.

Summary:
Approximately 9 miles and 2800 ft of ascent.
Section 1 – mainly stoned tracks to Cwm Eigiau quarry.
Section 2 – craig ascent & ridge-walk – mixed rock & grass, some exposure.
Section 3 – descent – unmarked pathless heather & grass.
Allow 6+ hours for an enjoyable day.

The attached map shows our approximate route; given the nature of the terrain you may wish to modify this to suit your own needs. There are several rocky traverses that would become quite challenging in wintry conditions and the potential drops are significant; please be well equipped for the conditions and be confident in your own skills.

Approach:
Take the B5106 alongside the Afon Conwy to Tal-y-bont. In the village turn west up the single track lane to Llyn Eigiau. Note: During snowy spells the lane may become a challenge, even for well shod 4x4s. Park in the car park at the end of the road, SH 732 663.

Walk:
Leave the car and walk down the access track to Llyn Eigiau. The break in the dam wall that caused the 1925 disaster, resulting in the loss of 16 lives, can be noted on the right of this track.

Craig Eigiau towers up behind the broken dam wall of Llyn Eigiau.
Craig Eigiau towers up behind the broken dam wall of Llyn Eigiau.

Continue onward until meeting the main dam wall, at which point turn left over a bridge and then right to follow the lower path along the left side of the wetland. After a short while follow the main path as it crosses the valley floor to the right and bridges the Afon Eigiau.

Crossing Afon Eigiau and the marshy area that would have been flooded when the dam was built.
Crossing Afon Eigiau and the marshy area that would have been flooded when the dam was built.

The track now climbs steadily upwards in to Cwm Eigiau, passing by a small lone dwelling. It is well worth pausing to look back at the view of the valley, as well as keeping an eye open for the Carneddau ponies that live here.

Looking back along Cwm Eigiau from the upper quarry track.
Looking back along Cwm Eigiau from the upper quarry track.

In due course you will come to the old quarry at the end of this track. At this point, we now need to swing right and proceed northerly up the rough grass slope, heading for the waterfalls that feed the Afon Eigiau and located on the north-eastern edge of the craig.

The old quarry workings at the head of Cwm Eigiau with Craig yr Ysfa beyond.
The old quarry workings at the head of Cwm Eigiau with Craig yr Ysfa beyond.

Skirt the left-hand side of this small cascade and head uphill amongst grass & boulders to reach a small plateau. We paused here for a few snacks before moving on again. From here the going is both rough and steep heading up to the higher plateau of Penywaun-wen, beneath the summit of Carnedd Llewelyn. After a careful clamber up to this point, we found it to be a good place to pause for some lunch. The views around are stunning, Carnedd Llewelyn immediately to the NW, Cwm Eigiau down to the east, Tryfan & Glyderau to the SW – you may even spot Snowdon beyond.

The shimmering blue waters of Ffynnon Llugwy.
The shimmering blue waters of Ffynnon Llugwy.

Now continue south-easterly along the ridge to Bwlch Eryl Farchog and then up to Pen yr Helgi Du. This section does include a short stretch, that some consider to be a scramble; if wearing a backpack, as we were, you’ll definitely want to be ‘hands on’. Furthermore in windy / icy / snowy conditions even more care should be taken – its not desperately narrow but the drops are big. Once at the Pen yr Helgi Du end, you can enjoy the view back of what you’ve just crossed.

Looking back across Bwlch Eryl Farchog on approach to Pen yr Helgi Du.
Looking back across Bwlch Eryl Farchog on approach to Pen yr Helgi Du.

Having negotiated the rocks to Pen yr Helgi Du summit, there is a more relaxing & grassy descent to a ladder style at the top of Bwlch y Tri Marchog, before climbing the grassy bank of Pen Llithrig y Wrach (Peak of the slippery Witch), what a name! More interesting views open up from here, especially looking north over Llyn Eigiau, past where you parked, to the N. Wales coast and its offshore windfarm.

Looking north from Pen Llithrig y Wrach over Llyn Eigiau to the North Wales coastline.
Looking north from Pen Llithrig y Wrach over Llyn Eigiau to the North Wales coastline.

It’s now time to descend. We headed NE at first, before heading towards the disused quarry workings. There are no paths here, it is rather damp walking across boggy heather. At the old quarry (care needed), pick up the path that will quickly lead you back to the original outgoing path. Now simply retrace your earlier steps, back to the car parking. See below for a few further photos and for the route map.

You may also enjoy my earlier blog post “Carneddau Ponies” with pictures of the ponies that live on this highland region of Wales.

Altitude:

CwmEigiau-walkprofile
CwmEigiau-walkprofile

Map:

Gallery: