Smart Motorway gantry sign
A gantry structure spanning the motorway with electronic signals, blue signs showing an exit and the following text.
Exit destinations: A505 Luton (C); Dunstable (C) .
Forward destinations: The NORTH, Milton Keynes; Dunstable (N) M1 .
Junction number: 11.
The original junction for Luton and Dunstable, now hemmed in by suburbia. The M1 now forms a sort of border wall between the two towns.