One of the few new cross-country routes created in recent years, the A417 and A419 together form a strategic link between the M4 and M5, connecting Swindon, Cirencester, Cheltenham and Gloucester, and longer distance destinations via the two motorway corridors.
From Swindon to the Air Balloon Roundabout south of Cheltenham, the dual carriageway follows the line of Ermin Way, a Roman Road that lends the route a remarkably straight course as it bounces across the hills of south Gloucestershire. There are gentle deviations left and right in various places to provide a bypass for the occasional town or village, but the road noticeably returns to the same straight line after each one.
Around Cirencester, the route gets itself into a bit of a tangle. The physical road itself is extremely simple - the dual carriageway continues non-stop around the town on a modern bypass. But its number gets a bit lost. This is where the changeover occurs between A417 and A419, but the A417 travelling in from the south-east doesn't have a junction with the bypass, so the A417 appears to be discontinuous. There is also a section of the bypass, between Driffield Cross Roads and Burford Road, where it would be hard to argue that either number could apply.
Because this route seems only to have had attention paid to it relatively recently, it's not quite finished. On the A417, there is an obvious gap near the Gloucester end of the route. Here the road becomes single carriageway for three steeply sloped and twisting miles, culminating in the Air Balloon Roundabout at the bottom of the hill where the road doubles back on itself. Highways England now has plans to fix this - but it won't be an easy job.