LNER A3 4-6-2 No 60102 Sir Frederick Banbury at the small stabling and coaling sidings provided at Marylebone in c1955.
Not sure if the loco is in BR blue - the lack a reverser 'reach rod' under the footplate indicates it is still 'right hand drive'; the rebuilding occured in February 1953.

Photo: W.J. Reynolds / Rail Archive Stephenson