The motorway, which has a total length of 327 km (203 mi), starts at a junction with the N104 Francilienne near Attainville in Île-de-France and ends at the Belgian frontier near Bray-Dunes, serving en route Beauvais, Amiens, Abbeville, Boulogne-sur-Mer, Calais and Dunkirk in Hauts-de-France.

The vast majority of the motorway was built in the 1990s to relieve the congested RN1 between Paris and the Côte d'Opale (Boulogne and Calais).

An 8 km southern extension between l'Isle-Adam and Attainville to a junction with the Paris ring road N104 (Francilienne) opened in 2020.

From Boulogne to the Belgian border the road is managed by the Direction Départementale de l'Équipement (DDE), which does not impose a toll.

This leads to speculation that the southern end of the motorway is intended to be extended either directly south by upgrading the RD301/RN1 to meet the A1 at Saint-Denis, Seine-Saint-Denis, or to the east by upgrading the RN104 to meet the A1 at Paris-Charles De Gaulle, thus completing the missing junction numbers.