The location is the extended Woodhead station which was adjacent to the south end of the tunnel of the same name. The train in the background is running 'wrong line' which implies that the other tunnel is closed for some reason (probably engineering work), plus the wires are up and the new line is fully ballasted - so this must be around the time of the changeover from the old to the new tunnels.
There are a couple of significant details in the image. First of all, on the tunnel mouth, just to the left, you can see the plaque commemorating the opening of the tunnel on June 3rd by Sir Alex Lennox-Boyd, Minister of Transport and Civil Aviation. Next, to the right of the tunnel, you can just make out some footsteps. These led to a raised platform where the Minister stood to give his address. by a process of deduction the date can be narrow to between 30th May and 11th June 1954.
[Mike Morant collection]