Dinas Rock

Dinas Rock (Welsh: Craig y Ddinas, "Fortress Rock") is a high promontory of Carboniferous Limestone which rises between the Afon Mellte and its left-bank tributary, the Afon Sychryd on the border between the county of Powys and the county borough of Neath Port Talbot in south Wales. It can be found near the village of Pontneddfechan near Glyn Neath at the head of the Vale of Neath. It derives its name from the presence of Iron Age earthworks on its summit, dinas in Welsh signifying a defensive site or "city".

Dinas Rock lies within the Brecon Beacons National Park and the Fforest Fawr Geopark. It is owned by Natural Resources Wales, who manage it for its wildlife interest and recreation. The mineral rights (and thus relicts of former mining and quarrying) are owned by Natural Amenities Ltd, a body concerned with the preservation of mines. The deep gorges which define its northern and southern edges are designated as a part of the Coedydd Nedd a Mellte (Neath & Mellte Woodlands) Special Area of Conservation (SAC) on account of their thick oak and ash woodlands, which shelter important bryophyte communities, in particular certain species of moss. The woodlands are also designated as a part of the Dyffrynoedd Nedd a Mellte a Moel Penderyn (Neath & Mellte Valleys and Moel Penderyn) Site of Special Scientific Interest.

The landform has been re-shaped by the extraction of limestone and by the nearby mining of silica rock and its transport down-valley by various means. The former limestone quarry is now a car park; its walls are used by climbers and abseilers. The Dinas Rock Silica Mines just to the east of Dinas Rock itself used to provide large quantities of very pure crushed sandstone destined for the manufacture of refractory bricks for furnace linings and the like. A system of tramways, aerial cableways and inclines on the southern flanks of Dinas Rock conveyed the material from the mines to the valley below.

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