Waun Fach

Waun Fach, at 810 meters, is the highest mountain in The Black Mountains and offers stunning panoramic views over the Beacons and plains towards Hereford. There is also a wonderful Iron Age fort to explore that stands guard over the Rhiangoll Valley.

The route we will take will return via Y Grib, a ridge offering superb views and sense of what ridge walking can offer – in this case it is quite broad, making it accessible and easy going, ideal for anyone wanting to experience a ridge for the first time.  Looking from the car park, you can see why this area is called “The Dragons Back”

Confusingly, there are two areas of the Beacons known as “The Black Mountains”. In Welsh “Mynydd Du” is to the west, but Waun Fach lies in “Mynyddoed Duon” to the east.

The start point to this walk is on the A479 3-4 miles south of Talgarth at a place called Pengenffordd. The car park, which is part of the Castle Inn, is clearly marked for walkers, and is separate from the pub /hotel car park.

BaldHiker Retreats

There is an honesty box for payment, but please note that there is a CCTV covering the car park and signs saying they monitor who is being honest with dire consequences for those who are not!

Waun Fach track view

Castle Inn to Pen Trumau via Rhiw Trumau

At the north end of the car park is a finger post pointing towards some steps, walk down these steps and onto a broad track. Should you wish to do this walk in reverse, turn left and walk up the hill. For now, we will turn right and walk down the hill. This is a pleasant walk down through trees ending at a small ford.

Join the narrow country lane and walk past the riding school at Cwmfforest. As you walk along this lane, you have lovely views of the way forward and start to appreciate challenge that’s before you!

The car park is at ca 320metres in height and in the kilometre or so, you have walked the altitude has dropped to 250 metres. Now in a little over a kilometre you will climb to over 600 metres, so be prepared for some steep sections. However, the benefit of this are the views down towards the Usk valley and back over Myndd Llangorse, so take your time, rest often and bask in this beautiful scenery.

usk valley landscape

As the country lane flattens out and turns right,  will walk up the signed bridleway. The path at this stage is obvious, just keep heading upwards and enjoy the views.

After a kilometre, the path starts to flatten off, although still rising, and becomes less distinct as the ground changes from bare rock to grass. This area can become very muddy and you cross many small streams. You will cross several footpaths heading north but keep aiming for a cairn on the crest of the hill in the easterly direction.

When you reach the cairn at Rhiw Trumau, take a well-earned rest and enjoy the scenery around you. Your path lies to the north and you will see the shoulder of Pen Trumau that you need to climb. From a distance, this looks quite daunting, but though the final section is steep, the path is well marked and can be walked up without the need for any handover hand scrambling.

dog on summit

Pen Trumau to Waun Fach

The walk now flattens out as you reach the plateau of Pen Trumau at 700 meters. The footpath is well marked and easy to follow. Indeed, the way forward has been laid out by the Brecon Beacons National Park, to minimise erosion to this delicate and fragile landscape, so please keep to the path.

I should also remind you of the need to be prepared for the mountains – suitable clothing, good boots, compass, and map, plus food and water. When I did this route, we set off in warm sunshine and blue skies, by the time I reached this plateau, visibility had reduced to 20-30 metres and the temperature had dropped significantly.

Follow the path as it rises gently toward the peak of Waun Fach. The top is marked by a cairn and intersection of multiple paths. I am told that on a clear day you can the Shropshire Clee Hills, look over the Brecon Beacons and Carmarthen fells and sometimes glimpse the Bristol Channel. But not today, the best I can give you is Barney, my Border Collie, investigating the cairn!

view from waun Fach

Waun Fach to Y Grib via Pen Y Manllwyn.

Now check your map and compass to ensure you take the correct path off Waun Fach. The paths are still well defined and you quickly drop down to ca 750 metres and in my case into clearer skies, so that on your left shoulder you have stunning views down Twyn Mar to the farmstead at Grafog, a  lovely sense of the descent on Y Grib and the views to Telgarth and beyond. Follow the broad path round Twyn Mar to the cairn at Pen Y Manllwyn, at the T Junction, take the left hand path down onto Y Grib.

waun Fach y crib

The descent of Y Grib follows a series of steps – sections of broad plateau followed by short steep descents. The plateau narrows but never becomes a true ridge, and the steep sections, whilst on approach can look a little daunting as though the decent is near vertical, there are always clear paths with well-defined ways down avoiding the need for any “bottom first” type descents!

Pause for breath before each steep section and enjoy the scenery around you, the descent offers ever changing views from Waun Fach round to Llangorse lakes, down to the Usk valley and northwards over the planes towards Builth Wells.

Waun fach descent

Castel Dinas

As you approach the final plateau of Y Grib at  490 metres, take time to look straight forward at the magnificent ruins of the mediaeval castle of Castel Dinas, built on an iron age fort. You can see an obvious path leading to the remains of the castle and it is well worth a visit.

Castel Dinas, or more correctly, Castell Dinas Bran was built in the 1260’s by a prince of Powys, Gruffydd Maelor 11. The name Castel Dinas Bran has been translated as “crow’s fortress” or “fortress of Bran”. There are other versions of the meaning of the name, but I’m sticking with “Crows Fortress” as it gives a real sense of drama that somehow fits with this area – Think “Lord of the Rings” meets “Game of Thrones”.

castel dinas

Building a castle on this rugged hill seemed ideal. It feels as though it would be impenetrable, commanding views for miles around, and you would be able to watch any approaching visitor, with plenty of time to decide if they were friend or foe and prepare a welcome accordingly.

When you have finished exploring the castle, return on the path down towards the bottom of Y Grib, go through the gate and follow the rough track down towards the farm. Once past the farm keep on the farm road until you nearly reach the main road. On your left is a bridleway, take this track and you will shortly reach the steps to the car park.

view down to the bottom Waun fach

You will have completed 8 miles or ca 12.3Km. The walk is moderate depending on your levels of fitness, but once you have completed the ascent towards Pen Trumau, the walk becomes a lot less strenuous, and the paths are well maintained and easy to follow.

The effort is rewarded by stunning views and the descent via Y Grib is just wonderful.

Route Details and GPX

Distance: 8 miles

Difficulty: Moderate

Parking: Dragons Back Car Park, A479, Pen-y-wern, Talgarth, Powys, Wales, Postcode – LD3 0EP

Download the Route GPX for Waun Fach

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  1. As ever, an interesting read Mick. Great photos too – Cheers!

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