Viaduct, gorge and trail
Pontsarn
A small Taf Fechan settlement where railway engineering, wooded limestone scenery and a traffic-free trail meet above the Blue Pool.
- Best for
- Limestone scenery and railway history
- Give it
- A walk and an unhurried pub stop
- Don't miss
- The seven arches of Pontsarn Viaduct
The Fox verdict
A railway landmark above a limestone gorge
Pontsarn concentrates a remarkable amount of landscape and industrial history around the Afon Taf Fechan.
Come for the seven-arch viaduct and the Blue Pool, then follow the Taff Trail or the longer circuit through the Taf Fechan Nature Reserve. The Aberglais Inn gives the visit a natural finish beside the trail.
Where to go
Places in Pontsarn
Every place below is checked against a published source, listed with what it is and how long to give it.
Local signatures
3 placesPontsarn Viaduct
Seven limestone arches carry a straight, 138-metre deck above the Afon Taf Fechan; built for the Brecon and Merthyr Railway, it now carries the Taff Trail.
- Visit length
- Editorial estimate: allow around 30 minutes
- Locality
- Pontsarn
Taf Fechan Nature Reserve and Blue Pool
The official circuit follows a historic leat and old maintenance tracks through ancient woodland and a limestone gorge to the Blue Pool, with waterfalls and rapids along the way.
- Visit length
- Editorial estimate: allow around 2 hours
- Locality
- river gorge between Pontsarn and Cefn Coed
- Access
- The longer official circuit has steeper sections and sometimes uneven, muddy ground.
Aberglais Inn
A renovated nineteenth-century stone hostelry with a small oak-floored bar, stone fireplace and log burner, plus a river-facing restaurant looking towards the Blue Pool.
- Visit length
- Editorial estimate: allow around 75 minutes
- Locality
- beside the Taff Trail, Taf Fechan Nature Reserve and Blue Pool
- Access
- Dogs are welcome in the pub, but not in the restaurant.
Food & drink
1 placeCrosswoods
An independent bakery and delicatessen established in 1929, making pasties, pies, cakes and cooked meats on the premises alongside sandwiches and salads.
- Visit length
- Editorial estimate: allow around 20 minutes
- Locality
- Merthyr Tydfil town centre
Walks & outdoors
2 placesTaff Trail / National Cycle Network Route 8
A 55-mile Cardiff Bay-to-Brecon route whose Merthyr section runs between Abercynon and Pontsticill Reservoir and crosses Pontsarn Viaduct.
- Visit length
- Editorial estimate: allow around 1 hour
- Locality
- crossing Pontsarn Viaduct
- Access
- The Merthyr section is predominantly traffic-free and graded easy to moderate for walkers, cyclists, runners and horse riders.
Morlais Circular Walk
A 6.3-kilometre circuit with 179 metres of ascent, linking the remains of thirteenth-century Morlais Castle with Pontsarn Viaduct.
- Visit length
- Editorial estimate: Allow around 1.5 hours
- Locality
- linking Morlais Castle and Pontsarn Viaduct
History & heritage
3 placesSt Gwynno, Vaynor
A late-1860s church paid for by ironmaster Robert Thompson Crawshay, with multicoloured stonework, stained glass and Crawshay's eleven-ton granite grave slab in the churchyard.
- Visit length
- Editorial estimate: allow around 45 minutes
- Locality
- Vaynor
Pont Sarn Bridge and Mill Remains
The bridge marks a Roman-road crossing; nearby are the remains of an eighteenth-century corn mill and fulling mill, with one original millstone surviving.
- Visit length
- Editorial estimate: allow around 45 minutes
- Locality
- by the Blue Pool
Cyfarthfa Castle, Museum and Art Gallery
A Grade I castellated house built in 1824 for ironmaster William Crawshay II, with displays on Merthyr's industrial and social history.
- Visit length
- Editorial estimate: allow around 90 minutes
- Locality
- Cyfarthfa Park
Things to do
1 placeBrecon Mountain Railway
Steam trains run from Pant through Pontsticill and beside Taf Fechan Reservoir to Torpantau, with all-ages journeys and visitor facilities at Pant and Pontsticill.
- Visit length
- Editorial estimate: allow around 2 hours
- Locality
- from Pant through Pontsticill and beside Taf Fechan Reservoir
- Access
- The café, outdoor seating and children's adventure playground at Pontsticill are available on railway operating days.
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Three ways to explore Pontsarn
Signature outings
Crawshay's stark memorial
See St Gwynno's multicoloured stonework and the eleven-ton granite slab over Robert Thompson Crawshay's grave, inscribed “God Forgive Me.”
Roman road and millstone
Find the bridge by the Blue Pool that marks the Roman-road crossing, with eighteenth-century mill remains and a surviving original millstone nearby.
Steam through Pontsticill
Take an all-ages steam journey from Pant through Pontsticill and beside Taf Fechan Reservoir towards Torpantau.
The village story
Pontsarn Village Guide
Eight unchanged paragraphs follow the viaduct, gorge, trail and inn into Pontsarn's railway, Roman-road and Crawshay stories.
Viaduct and limestone gorge
Seven limestone arches carry the Taff Trail across the Afon Taf Fechan here, a hundred and thirty-eight metres of straight deck standing nearly thirty metres above the water. The Pontsarn Viaduct was built in 1866 and opened the following year to take a railway, and although the deck was laid wide enough for double track, only a single line was ever installed. Now it carries walkers and cyclists.
Below the road bridge the Blue Pool sits in a gorge the Afon Taf Fechan has cut through limestone over a very long time. Cliffs, ancient woodland, rapids and waterfalls fill the Taf Fechan Nature Reserve, a two-and-a-half-kilometre stretch of river between Pontsarn and Cefn Coed. Visit Merthyr calls it "one of the most remarkable landscapes in Merthyr Tydfil."
An inn beside the trail
The Aberglais Inn stands above the trail, a renovated nineteenth-century stone hostelry with a small bar — oak floor, a handmade oak bar, a stone fireplace and a log burner — and a river-facing restaurant that looks toward the Blue Pool. The bar seats about twenty-two, the restaurant about twenty-eight. Two Felinfoel cask ales are usually on: Double Dragon, a 4.2% session bitter, and Dragon's Heart at 4.5%. There is a lawn garden, parking opposite and a quiz on Thursdays.
From the pub the Taff Trail runs in both directions, the fifty-five-mile route between Cardiff Bay and Brecon; its Merthyr section is predominantly traffic-free. The longer Blue Pool circuit begins down at Cyfarthfa Park and follows an old waterworks leat through the trees to the pool before climbing to the Aberglais and returning along the trail; it takes in waterfalls and rapids, and gives you uneven, muddy ground to negotiate on the way. A shorter walk of 6.3 kilometres links the viaduct with the thirteenth-century remains of Morlais Castle. The village itself is reached by a minor road between Trefechan and Pontsticill, and Stagecoach's route 25 from Merthyr stops here, at a point still listed as Pontsarn Inn. Merthyr Tydfil has the nearest railway station and trains to Cardiff.
Railway and Roman-road remains
Pontsarn once had a station of its own, and for a time it was one of the busiest on the line — for church and chapel Sunday-school outings. Passenger trains stopped in 1961, and the last train is recorded crossing the viaduct on 1 August 1966. Today only the platform survives beside the path.
The bridge by the Blue Pool sits on an older route still. Its name, Pont-sarn-hir, means "the bridge of the long paved road," a reference to the Roman road that crossed here on its way from the fort at Brecon down to Cardiff. Nearby are the remains of an eighteenth-century corn mill and a fulling mill, both once owned by the Harris family, and one of the original millstones is still there.
St Gwynno and provisions
The parish church, St Gwynno at Vaynor, was built in the late 1860s and paid for by the Cyfarthfa ironmaster Robert Thompson Crawshay. It has multicoloured "crazy paving" stonework, a red pantile roof and stained glass including work attributed to Joseph Bell and A. L. Wilkinson. Crawshay lies in the churchyard under an eleven-ton slab of granite carved with three words: "God Forgive Me." The battlemented tower of the old church survives nearby; local tradition holds that its medieval building was replaced in 1295 and kept in use for roughly six hundred years.
For provisions you go into Merthyr, where Crosswoods, established in 1929, now makes pasties, pies and cakes on the premises. But on a cold day the reason to be here is the log burner in the small bar, where dogs are welcome, but not in the restaurant.
Stay around Brecon Beacons
Make a longer stay of it
Travel Fox holiday homes around Brecon Beacons, linked directly to their property pages.
A guide with a point of view
Written from research. Edited for real journeys.
Use the Official site links for live practical details, then use this guide for context, ideas and room to explore.
Sources
Every place on this page is checked against a published source. Each entry links the record we used and names who publishes it.
- Pontsarn Viaduct — visitmerthyr.co.uk operator, sector body or destination organisation
- Taf Fechan Nature Reserve and Blue Pool — visitmerthyr.co.uk operator, sector body or destination organisation
- Aberglais Inn — aberglais.online operator, sector body or destination organisation
- Taff Trail / National Cycle Network Route 8 — visitmerthyr.co.uk operator, sector body or destination organisation
- St Gwynno, Vaynor — churchinwales.org.uk other published source
- Morlais Circular Walk — stagecoachbus.com other published source
- Pont Sarn Bridge and Mill Remains — visitmerthyr.co.uk operator, sector body or destination organisation
- Crosswoods — sttydfilshoppingcentre.co.uk other published source
- Brecon Mountain Railway — bmr.wales other published source
- Cyfarthfa Castle, Museum and Art Gallery — visitmerthyr.co.uk operator, sector body or destination organisation