Disused box fully lit and functional?
Ding, Ding, Ding - we have a winner... (Although, to be fair, The Edge almost had it too but lost on account of his wording).
Stobcross was closed along with the entire low level line for some time. A year and a bit later, a supervisor/foreman/inspector was sent to have a look at the condition of the place and noticed the box fully lit up. Upon going over and going inside, he noticed a signaller inside. It turns out that all of the other bobbies on the line had either taken retirement or moved on to other jobs - except this guy. Seems he had been forgotten about and, obey the last instructions he had been given, turned up to do his normal shift and kept the box working and operational, signed in the register when he came on and off duty, submitted the books for inspection and collected his pay as normal. Apparently, nobody had been any the wiser... The story goes that, when told by the supervisor/foreman/inspector to close the box, the signaller did so by sending the traditional box closing code, recorded the fact in the box's register and had the guy countersign it!
Have to say this has been a very good one for you to all try and guess - it was a close run thing at the end, but BestWestern just squeaked in based on wording - the floor is his