The first vehicle is an ancient 1906 GWR ten comparment concertina all 3rd coach to Dia C27 presumably added as a strengthener. Paul Warner says There's not a lot to go on in this photo, but just looking at it says to me Grafton East Junction. I'm just going by the fact the train appears to be running downhill on a left hand curve (towards Crofton and Bedwyn), the telegraph poles are on the up side, the way the land gently rises towards the trees in the distance, and the signal wire in the foreground Peter Kerslake adds I would suggest a date of between 1951 and 1956 for this view of Old Oak Common's 70020 Mercury.