London (SE), Swanley
Smart Motorway gantry sign
A gantry structure spanning the motorway with electronic signals, blue signs showing an exit and the following text.
Exit destinations: A20 [Hollow triangle diversion symbol] London (SE), Swanley.
Forward destinations: (M23, M3, M4) Gatwick [Airport symbol]; Heathrow [Airport symbol] Bromley (A21) M25 .
Junction number: 3.
Here's your second bite at the junction 3 cherry. The list of forward destinations is much the same as the last sign, but in a whole new order. You sometimes get the feeling that the people who put up signs on the M25 like to shuffle the place names into a new and random order every time they make a new one.