The 'Castle' class 4-6-0 locomotives designed by Charles Collett and built at Swindon Works were the principal passenger locomotives of the Great Western Railway. The 4-cylinder locomotives were built in batches between 1923 and 1950, the later examples being constructed after nationalization by British Railways. In total 171 engines of the class were built and they were originally to be seen at work all over the Great Western Railway network,...