Corn Du is a summit of the twin topped Pen y Fan and the second highest peak in South Wales at 873 m (2,864 ft), situated in the Brecon Beacons National Park. The summit itself is marked by a well structured Bronze Age cairn with a central burial cist like that on nearby Pen y Fan. The two summits are visible from great distances owing to their height above the surrounding moorland, and are famous landmarks. The views from the peaks are also panoramic and very extensive, the Black Mountain and Fforest Fawr being especially obvious to the west. Mynydd Epynt is visible to the north behind the county town of Brecon, and other parts of the escarpment to the east.