The Countryfile team explore the Cambrian Mountains, one of Wales' best-kept secrets, nestled between its more famous neighbours - Snowdonia and the Brecon Beacons. Matt Baker takes to the saddle to help round up sheep on the hills and meets the farmers trying to put Welsh mountain lamb on the foodie map. John Craven discovers why writers and artists have taken inspiration from the landscape. He puts his painting skills to the test when he joins a local arts group. In the Elan Valley, Jules Hudson finds out about one of the largest Victorian engineering complexes in its day: a series of dams built to hold back Welsh water destined for the taps of Birmingham. Elsewhere, Julia is in Kent, putting her fears behind her to find out about a ground-breaking conservation project; and Adam gets a day off from the farm to visit a project where working horses have become more useful than a tractor. Tom Heap investigates claims that the illegal use of lead shot is leading to the unintentional deaths of wild animals.