GWR Hall 4-6-0 No 5907 Marble Hall with the up 'Cheltenham Spa Express' passing Pangbourne on 20 August 1956.
Peter Kerslake says "Perhaps they were short of 'Castles' on this day at Gloucester Horton Road and the Shedmaster has been obliged to put his nicely turned out 5907 'Marble Hall' onto this Top Link working to Paddington with its tightly timed dash from Swindon even with clearly a substantial load to contend with as well."

Photo: D.M.C. Hepburne-Scott / Rail Archive Stephenson