What do you mean, you've never seen a freight locomotive on the London tube? This was Southern Railway no. 75S, and was used to shunt coal wagons from the 1890's to the 1960's, according to display material at Shildon.
Location: NRM Shildon
Original line: Waterloo and City Railway
Photographer: Ken Strachan
Contact photographer: Ken Strachan
Date: 03/08/2017
Image number: 61087