Starting on Anglesea with nuclear trains, we cover the Principality from top to toe, ending in Pembrokeshire. The Welsh railways have always been famous for the vast quantities of coal hauled down the Valleys to the industrial areas of South Wales and these are covered in depth. Dedicated diesel types were produced from the British Railways' First Generation classes for this traffic. We see classes 03, 20, 25, 31, 46, 47 and 58 as well as others on public and private railways alike. This fabulous programme, part of a wonderful eight-volume series, celebrates the might of diesel, an often overlooked part of British rail heritage. Incredible action footage makes every title in this series a real treat.