The A2219 follows the original route of the A23 through the centre of Crawley, although the road spent many years as the B2125.
The road starts in the Northgate area of town at a roundabout at the northern end of the A23 bypass, where it also meets the A2011, which links to the M23. The road heads southwards along London Road, which starts off residential but soon runs through an out-of-town retail park, which leads to the town centre. After meeting the High Street (a remnant of the old Crawley) the road reaches a one-way loop. Southbound traffic continues along the High Street before the old line of the A23 ahead is blocked (the remainder of the High Street is partially pedestrianised) and so is obliged to turn right and join Pegler Way, where it meets the northbound carriageway again.
The road proceeds as a dual carriageway along what is now the inner ring road (whose northern side is missing). The A2220 (former A264) is met at the next roundabout and the A2219 is the dominant partner in a multiplex along the next section of ring road to reach a gyratory, where the two roads diverge. Southbound A2219 traffic goes round three sides of the gyratory, rejoining the ex-A23 just in time to go over a level crossing. The railway line here looks surprisingly old for a new town, with a signal box painted in BR Southern Region colours and with the overgrown platforms of the original Crawley station adjacent.
We continue south through the suburbs, now on Brighton Road. The road becomes remarkably leafy and it seems as though we have entered open country. We haven't – main roads in New Towns tend to bypass residential areas. The houses soon come back and our route ends at a T-junction on the A2004, just a few yards east of its junction with the A23.
An amended OpenStreetMap trace for this route awaits uploading to the SABRE Wiki.