Powys covers the historic counties of Montgomeryshire and Radnorshire, most of Brecknockshire, and a small part of Denbighshire — an area of 5,196 km², making it the largest principal area in Wales by land area.

The majority of the Powys population is made up of small villages and towns with the largest, Newtown, having a population of just over 12,000. Most of the area is mountainous, with north-south transportation by car being scenic but slow.