OS Explorer Maps OL12 & OL13 The Brecon Beacons are a series of mountains in South Wales, but the National Park covers a larger area and includes a number of towns and villages. There are activities both on land and water, and the area designated as an International Dark Sky Reserve holds regular stargazing events. This map bundle contains both OS Explorer Maps for the National Park with a discount of 20% compared to the cost of buying them individually, and is available in both standard and weatherproof \'Active\' versions. Whatever activities you plan on your visit, you can make the most of it with Ordnance Survey maps.