LNER N7 0-6-2T 69621

Designed for the GER, the loco was built at Stratford in 1924 and was originally numbered 999E. London Liverpool Street suburban duties was the original stamping ground, the locomotive was withdrawn from BR in the 1960's. Normally resident on the North Norfolk Railway, the engine was last overhauled in 2005.
Apologies for the ghostly aparitions at the bottom of the photo - my flash caught 2 people very brightly making them rather dominate the photo, so I had to try to dim them down a bit (not entirely successfully).

Photo (at Barrow hill roundhouse) DGC.