Fan y Big (Welsh: Welsh pronunciation: [van ə ˈbiːg]) is a subsidiary summit of Waun Rydd in the Brecon Beacons National Park, in southern Powys, Wales. It is 716.6 m (2,351 ft) high and is often hiked as part of the Horseshoe Walk, a traverse of the four main peaks in the Brecon Beacons.