Map sheet number OL12 in the Explorer map series is the ideal map for those seeking outdoor adventure. The landscape of the Brecon Beacons attracts walkers, cyclists and riders to its rolling hills, valleys, caves and waterfalls. Highlights include: The Beacons Reservoir, Brecon, Fan Faw, The Black Mountains, Brecon Canal, Merthyr Tydfil, River Towy, and Trecastle.