Plynlimon, or Pumlumon in Welsh, is the highest point of the Cambrian Mountains in Wales, and the highest point in Mid Wales. It is a massif that dominates the surrounding countryside and is the highest point of Ceredigion.

The Cambrian Mountains are a series of mountain ranges in Wales. The term Cambrian Mountains used to apply to most of the upland of Wales, and comes from the country's Latin name Cambria. Since the 1950s, its application has become increasingly localised to the geographically homogeneous Mid Wales uplands, known in Welsh as Elenydd, which extend from Plynlimon (Pumlumon) to Radnor Forest in the east and Mynydd Mallaen to the south. This barren and sparsely populated 'wilderness' has been referred to as the Desert of Wales. The area includes the sources of the River Severn and River Wye and was unsuccessfully proposed as a national park in the 1960s and 1970s. The highest point of the range is Plynlimon, at 2,467 feet (752 m).