The "Clockwork Orange" as it's known by the locals is a subway network serving various areas of Glasgow city. It runs underneath the River Clyde and has two lines, running clockwise and counterclockwise in a loop covering areas such as Govan, Partick, Kelvinbridge and the inner city areas such as Queens Park and Buchanan Street.
It is a very simple rapid transit system but also the third oldest in the world... according to Wikipedia.
The image was taken on 35mm film (slightly expired ISO 400) hence the greened out effect on the fluorescent lighting. I quite like how that and the film grain turned out, so I have not colour corrected the image as the grit it portrays isn't far from the real thing. Of course, this is from before the subway stations were all refurbished with white walls and bright LED lighting prior to the commonwealth games (2014), and now it looks nothing like this.