CN410

Prince of Wales Quarry  

05/03/2020  

Designated  

Gwynedd  

Dolbenmaen  

254900  

349850  

Industrial  

Quarry  

Post Medieval  

The monument comprises the remains of Prince of Wales Quarry, Cwm Pennant. It is located at the north end of Cwm Pennant on the eastern side of the valley on the southern slopes of Trum y Ddysgl and was operational between the 1860s and 1886. At its peak in the late 1870s Prince of Wales Quarry provided employment for over 200 men producing an output of 5,000 tons of slate per annum. The quarry complex is spread over an area approximately 1km N-S and includes a series of quarry levels, inclines, tramway, slab mill, barracks, aqueduct, reservoir and the quarry manager’s house. Visually, the quarry is dominated by the hillside working which comprises seven working levels, each with evidence of both pit and underground-working at their eastern ends. The levels are connected to large ‘fingertip’ waste areas via a series of tramways and are inter-connected by a substantial counter balance incline. The levels retain the relict remains of weigh-houses, dressing sheds, offices, ancillary buildings and barrack blocks. One of the most prominent surviving buildings is the upper barracks, a terraced row of 4 double-fronted domestic structures, book-ended by single-room structures at the west- and east-ends and a single detached building to the rear of the west-end. The building complex is mostly roofless but survives to eaves height in a well-preserved, relict state. Two unusual circular ‘beehive’ blast shelters (now collapsed) are present on the lower levels. A railway formation cut into the western side of the valley connects the hillside working to a slab mill at the southern end of the site via a second counterbalance incline. The slab mill is roofless but retains all of its walls despite some localised collapse in the northern gable and the SW entrance. The southern gable stands to a height of c.6m. The mill is 25m N-S x 9m transversely, the principle elevations retaining 6 large entrance doors, 3 on the east elevation facing on to a slab yard (with some rail formation / sidings evident) and 3 opposing entrances on the west elevation facing on to a discrete area of tipping. The entrances are of a size to allow access for large pieces of slate slab, probably transported by waggon. The door reveals are dressed with decorative stone voussoirs and retain iron fittings for hanging doors. The southern end of the building retains a large (external) wheel pit for an overshot waterwheel which was fed from a reservoir via an aqueduct. A row of 6 evenly spaced monumental launder pillars are evident to the east of the mill which follow the watercourse up stream towards the dressed-stone dam and reservoir. To the west an impressive railway cutting marks the route of the 1877 extension to Cwm Dwyfor Mine. The cutting also provides access to the quarry manager’s house at Cwm Trysgl. The monument is of national importance for its potential to enhance our knowledge of the slate quarrying industry. Although it had only a relatively short working life, like the nearby Gorseddau Quarry (CN303), Prince of Wales saw substantial investment, not only in quarry development, but also in the water-power system and transport infrastructure both of which survive as testament to the ambition of the quarry owners. The remote nature of the quarry means that it survives in an exceptionally well-preserved and legible state, and it illustrates all stages of quarrying from extraction, processing, waste management and transportation of slate in one coherent system. The scheduled area is in four parts (A to D) and comprises the remains described and an area around them within which related evidence may be expected to survive. • Area A is located at the head of the valley. It comprises the extraction areas, upper incline and working levels within which are located the relict barracks and quarry shelters, the upper counterbalance incline, the principle working levels and their associated tips to the west. Area A is an irregular polygon 550m NNE-SSW by 285m transversely. • To the south, Area B includes the railway, the lower incline, the slab mill and its associated launder pillars. Area B is an irregular polygon following the route of the tramway for 600m NNE-SSW by 5m transversely. At its southern end Area B extends to 120m E-W x 40m N-S. • To the east, Area C includes the reservoir and dam. Area C is an irregular polygon 185m NNE-SSW by 85m transversely. • To the west, Area D comprises the Quarry Manager’s House and outbuildings at Cwm Trysgl along with the railway formation that connected the Prince of Wales Quarry to the nearby Cwm Dwyfor mine. Area D is an irregular polygon 100m WNW-ESE by 60m transversely.