Pen yr Ole Wen & Carneddau: route guide

Francesca Donovan takes a walk on the quiet plateaus of Eryri to the Carneddau via the famous stiles of Pen yr Ole Wen.

Here’s my unpopular opinion: I think Tryfan is best experienced from the “other” side of the Nant Ffrancon. If you’re looking for a big mountain day with space to roam, reach out and touch the sky, the Carneddau mountain range offers a charming, if less rugged, alternative just a stone’s throw away from the Glyderau’s imposing crags. And yet, ascending via Pen yr Ole Wen from the east (avoiding the relentless scree of its south face) still offers a decent little scramble up to those high, wide plateaus.

Here, on a calm, bluebird day you’ll be treated to views north out to sea as well as the summit of Yr Wyddfa to the south, beyond layer upon layer of mountain magnificence. Towering above Ffynnon Lloer, the Cambrian Way paves an expanse that allows you to stay high for longer. Passing the Ffynnon Llugwy reservoir on your return, you might even catch a glimpse of your altitude-induced grin in a mirror reflection as you descend back down into the crowds along the A5 and towards Ogwen Cottage.

Pen yr Ole Wen and the Carneddau: route description

Start/Finish: A5 layby parking (GR: SH 668605) | Maps: OS Explorer OL17 Snowdon/Yr Wyddfa (1:25k) | Ascent: 2,925ft/1008m | Distance: 9.1 miles/14.7km | Duration: 6 hours

1. SH 668605: From the A5 layby parking, cross the road to the signposted trail up to Pen yr Ole Wen. (Get there early for prime parking and minimal road walking.) Follow the track curving through sloped farmland, taking the signposted stone-stepped path up the hill bearing N, following Afon Lloer. Take your time picking your way up the sometimes-waterlogged section and on the river crossing.

Stop to cool off in the waterfalls, look back and marvel at Tryfan, watch the Ogwen Mountain Rescue helicopter drills.

Don’t forget to say hello to the Carneddau ponies, the only population of wild ponies in the UK.

After 1km, you’ll have to factor in time to snap the obligatory picture of the most photogenic stile in all of Eryri/Snowdonia.

In a further 0.2km, bear E to begin the ascent proper.

2. SH 666618: Following the start of the stony Cambrian Way path E, you’ll continue up Pen yr Ole Wen, ascending fast up a grade 1 scramble with simple navigation and a clear path up the rock face. It can be slippery, especially in ice, but you’re never too far away from a sturdy foothold here. Just remember to keep your eyes ahead for the first glimpse of Yr Wyddfa as it peeks up behind the Glyderau and towers over Llyn Ogwen. Continue up to the summit of Pen yr Ole Wen (978m) 1.2km away.

3. SH 655619: From the summit – an uninspiring cairn not representative of the incredible views south into Eryri and to Wales’ highest peak – continue NNE along the Cambrian Way. It’s littered with helpful cairns to aid navigation on days with low visibility, first guiding you to Carnedd Fach and, eventually, in 1.5km, to Carnedd Dafydd.

It’s a delight to pick your way along the minor rock boulders which offer chance to focus on footwork without any great challenge as you admire the views to Conwy Bay on your L and Ffynnon Lloer on your R down Cwm Lloer. Take a moment to rest in the figure of eight shelter on Carnedd Dafydd (1044m), often decorated with hoar frost in the winter months.

4. SH 663630: Bearing E, continue along Cefn Ysgolion Duon into the depths of the Carneddau. The summit of Carnedd Lewellyn (1064m) lies 3km away.

5. SH 683644: From Carnedd Llewellyn, bear ESE down Penywaun-wen. As you begin the descent to Bwlch Eryl Farchog, you may need hands and feet as you shuffle your way down this second easy scramble of the day. Backsides are acceptable modes of transport at this stage. After, you can enjoy the views down Criag yr Ysfa gullies and S into Eryri from this slim but manageable ridgeline path – firmly on two feet.

6. SH 694633: From here, you have two options. You can stay on track and enjoy a short scramble up to Pen yr Helgi Du, descending down Ty Braich. However, on this incredibly still day, we took a punt and skidded our way S down the steeper run to join a footpath alongside the Ffynnon Llugwy reservoir.

Here, the unusual choice not to stay high paid off as the glassy waters provided an incredible reflection of Craig y Llyn and a chance for a dip. From the bank of the reservoir, continue S until you reach a track and continue following this S and then SW until you reach the A5.

7. SH 687602: Follow the A5 W for 0.3km and turn L, following the campsite footpath until you reach the Snowdonia Slate Trail.

8. SH 685 601: Turn R onto the Snowdonia Slate Trail and follow this for 1.3km heading E, with Tryfan on your L. On a clear day, from this trail, look up and you can clearly see hillwalkers making the famous jump from the ‘Adam and Eve’ standing stones at its summit. After 1.3km, turn R off the trail and you’ll reach the A5 layby.

Further information

Tourist Information: Visit Eryri, 01766 770274

Public transport: The T10 Llew Jones International bus service stops at Ogwen Cottage

Nearest YHA: Idwal Cottage

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