A-road fork sign
A green sign with a diagram showing an exit branching off the road ahead and the following text.
Forward destinations: The NORTH; Stamford A1 .
Exit destinations: Stibbington; Sibson [Airport symbol]; Elton; Nene Valley; Railway; [Steam railway symbol] .
The Nene Valley Railway is reasonably long and has quite a few stations, so you'll see it pop up in all sorts of TV shows and films, and a music video for Queen where a steam train breaks through a slightly unconvincing polystyrene wall.