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Clydach Gorge

Running about three miles from Brynmawr down to Gilwern, the beautiful Clydach Gorge is a natural passage-way between the lush farmlands of the Usk Valley and the barren moors of Northern Gwent and Breconshire.  It is a site of Special Scientific Interest and has been exploited since prehistoric times as shown by the two claimed Iron Age forts that guard the entrance into the valley.  By the 17th Century the valley was becoming industrialised, the Llanelly furnace and forge had been established at Maes Gwartha and, by 1684 were producing large quantities of iron and charcoal.  By 1693 Clydach House had been built along with a number of workers’ cottages.  It was at Clydach House in 1841 that Sir Bartle Frere was born, a High Commissioner of South Africa who unwittingly helped start the Zulu wars.  The Clydach Iron Works, founded before 1795, followed the recent introduction of coke as fuel and up until the 1860’s employed over 1,350 people many being children under the age of 13.  The valley has the densest network of surviving early tram road routes anywhere in Wales, one of which was replaced by the Merthyr, Tredegar & Abergavenny Railway in 1862.  The Gorge is still an important connecting route for the A465 Heads of the Valley Road that runs on to Swansea, connecting the Midlands with the Irish Ferry system.


Eifion Lloyd Davies ©2015

Joby's Pitch

Joby ran a knackers yard under the road coming down into Brynmawr. The road was supported by arches and he had his business in one of them. - horses for cat food and glue.

Clydach Gorge from Gilwern Hill -  accessible from B4246 Blaenafon – Llanfoist Road

Viewed from Gilwern Hill looking north towards Brynmawr, this cleft into the limestone coal basin provided a natural link between Usk Valley and coalfield, and thus made the Brecon Canal commercially viable.          Utilised by mule trains, tramroads, turnpike, railway and modern roads, the gorge became the most intensively-used industrial route in Wales. Small-scale charcoal-fired furnaces and forges were established here in the 17th Century. In 1841, Sir Bartle Frere – South African High Commissioner instrumental in starting the Zulu Wars- was born at Clydach House near the family’s Clydach Ironworks.

The valley’s natural beech woods are now a “Site of Special Scientific Interest”.

Clydach Village

Black Rock

Until the A465 Road was completed in 1962, traffic from Brynmawr to Gilwern had to use this narrow road which had a steep gradient.

The A465 Heads Of The Valleys Road

This road was a single carriageway construction, and work began in March 1960, the road was opened to traffic in 1962

Dualling of the A465 Heads Of The Valleys Road

In late 2014, work commenced on widening the section of the road from Brynmawr to Gilwern to a dual-carriageway

Derek Brockway - Weatherman Walking - Brynmawr to Abergavenny

This walk starts in Brynmawr, and passes through the incredible Clydach Gorge, around quarried slopes and wooded cwms or hollows, and on to Abergavenny

– a distance of about 9 miles depending on where you choose to finish.

Much of the route is along the old trackbed of the former Heads of the Valleys railway line which operated from 1879 to 1958.

To download a PDF file of the walk, please click on the button to the right.

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