The A21 autoroute is a toll free highway in north western France it is also known as the Rocade Minière. It is long. Junctions Completed In construction Upgrade of N455 between Flers-en-Escrebieux and Pecquencourt which is the northern by-pass Douai. Proposed Upgrade of the N455 between Pecquencourt and Douchy-les-Mines and the A2. External links A21 Motorway on Saratlas A21 Nord (French department) Transport in Pas-de-Calais