With a maximum speed of , the line appreciably shortened rail journeys between Paris and Lille. Its extensions to the north (Belgium, the Channel Tunnel) and the south (via the LGV Interconnexion Est) have reduced journey times to Great Britain and Benelux and for inter-regional trips between the Nord (Pas de Calais) region and the southeast and southwest of France. Its route is twinned with the A1 for . As it is mostly built in flat areas, the maximum incline is 25 metres per kilometre (2.5‰). And the line was given its official nickname, The "A1 Highway".