Dates of operation 1862–1979 Locale Wales | Headquarters Nantlle | |
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Track gauge 3 ft 6 in (1,067 mm); 2 ft (610 mm) | ||
Pen-yr-Orsedd Quarry was a slate quarry in the Nantlle Valley in North Wales. It was one of the last slate quarries operating in North Wales and the last operating on the Nantlle area, finally closing in 1979.
History
The Pen-yr-Orsedd quarry was one of the major slate producers of the Nantlle Valley, supplying over 10,000 tons of product in 1864. It was also the last quarry in the vale that commercially produced slate, closing in 1979.
In 1862 the quarry was connected to the Nantlle Railway, with 3 ft 6 in (1,067 mm) narrow gauge lines extended to all but the highest levels of the quarry. Most levels of the quarry had both 3 ft 6 in (1,067 mm) narrow gauge and 2 ft (610 mm) narrow gauge trackwork, many with mixed gauge tracks. The Nantlle Railway connection was used up until 1963, while the internal 2 ft lines continued in limited use until the end of quarrying.