Smart Motorway gantry sign
A gantry structure spanning the motorway with electronic signals, blue signs showing a "tiger tail lane drop" where the left lane exits, the right hand two lanes continue ahead and the second lane from the left can go in either direction, and the following text.
Exit destinations: A421 Bedford; M. Keynes (S) .
Forward destinations: The NORTH, Milton Keynes M1.
Junction number: 13.
The first of two junctions for Milton Keynes, hugely upgraded over the years from a little Diamond junction for local traffic to the tangled mess of roundabouts and traffic lights that now exists. Once this has passed we're on a newer Smart Motorway with All Lane Running, so there's four lanes permanently open and less messing about through junctions.