The Cambrian Mountains are a series of mountain ranges in Wales.Originally the term "Cambrian Mountains" was applied in a general sense to most of upland Wales. Since the 1950s, its application has become increasingly localised to the geographically homogeneous Mid Wales uplands, known in Welsh as Elenydd, which extend from Pumlumon to Radnor Forest in the east and Mynydd Mallaen to the south. This barren and sparsely populated 'wilderness' is often referred to as the Desert of Wales.