The A417 switches to its permanent new layout at 6am on Friday 18 September and the Air Balloon roundabout is removed. Four nights of closures come first.

The Air Balloon roundabout is being taken out of the A417, and the road changes shape at 6am on Friday 18 September.

National Highways confirmed the date on 10 September. From that morning drivers will use the permanent new route built by the A417 Missing Link scheme, for journeys in both directions between Gloucester, Cirencester, Cheltenham and Oxford. The roundabout at the top of Crickley Hill, about ten miles north east of Stroud in the Cotswold district, goes with the switch.

For anyone in the Five Valleys this is the road to Cirencester, Oxford and the A40, and the change lands eleven days before the other eastern route out of the district closes. Cowcombe Hill shuts from 29 September to 9 October.

Four nights of closures first

To make the switch, the A417 is closed in both directions between the A46 junction at Brockworth and the Air Balloon roundabout:

  • overnight, 9pm to 6am, Monday 14 to Wednesday 16 September
  • overnight, 9pm to 6am, Thursday 17 September

The new A436 and A417 between the Air Balloon, the Ullenwood roundabout and the A429 Burford Road are shut as well on the night of Wednesday 16 September, 9pm to 6am.

A full weekend closure of the same A46 to Air Balloon stretch ran from 11pm on Friday 11 September to 6am on Monday 14 September. National Highways’ seven-day closure report labels that stretch A46 Shurdington rather than A46 Brockworth; it is the same closure.

Access for emergency services is maintained throughout, and signed diversions are in place. National Highways asks drivers to follow the signs rather than a sat nav, and says the switch date can move for weather or “unforeseen circumstances”.

What actually changes on Friday

The A417 before and after the traffic switch on 18 September 2026 Before 6am on Friday 18 September 2026, traffic uses a temporary route through the Air Balloon roundabout, and there is a direct route from Cheltenham and Oxford towards Gloucester. After the switch, the Air Balloon roundabout is removed, northbound traffic from Cirencester stays on the new A417 without leaving at Shab Hill junction, southbound traffic from Gloucester continues straight towards Cowley junction and Cirencester, and there is no longer a direct route from Cheltenham or Oxford to Gloucester: traffic uses the new A436 to Shab Hill junction and then either continues to Cirencester or takes the underpass to the northbound slip road. Access to Birdlip stays on the existing route through Cowley junction until the new B4070 opens later in 2026. Single-lane traffic management stays in place. The A417 at the Air Balloon, before and after 6am on Friday National Highways scheme update, 10 September 2026. Until 6am, Friday 18 September From 6am, Friday 18 September Traffic runs on a temporary route through the Air Balloon roundabout. A direct route runs from Cheltenham and Oxford towards Gloucester. Northbound traffic from Cirencester leaves the route at Shab Hill junction. The existing A417 between the Air Balloon and the B4070 was closed permanently in July 2026. The Air Balloon roundabout is removed. No direct route from Cheltenham or Oxford to Gloucester. Use the new A436 to Shab Hill, then the underpass. Northbound traffic stays on the new A417 all the way. Birdlip is still reached through Cowley junction until the new B4070 opens. Single-lane traffic management stays in place until later works finish. Graphic by Stroud Today
National Highways says delays are likely while drivers get used to the new layout.

The change that catches most people out is the loss of the direct run from Cheltenham and Oxford towards Gloucester over the top of the hill. From Friday that traffic uses the new A436 to reach Shab Hill junction, and then either carries on towards Cirencester or takes the underpass to the northbound slip road for Gloucester.

Going the other way, northbound drivers coming up from Cirencester stay on the new A417 instead of leaving it at Shab Hill. Southbound traffic out of Gloucester runs straight ahead towards Cowley junction and Cirencester, because the roundabout that used to interrupt it is no longer there.

Birdlip is unchanged for now. The new B4070 into the village and the northbound slip road at Cowley junction open later this year, so until then access stays on the existing route through Cowley junction.

National Highways warns that some delays are likely when the layout first opens, and that single-lane traffic management stays in place until further work is finished and more capacity opens up.

The scheme behind it

The A417 Missing Link fills the single-carriageway gap between the dual sections at Brockworth and Cowley, the stretch that produces the queues on Crickley Hill. National Highways calls it a landscape-led scheme through the Cotswolds National Landscape. Work started in early 2023, the published end date is 2027, and the cost is given as £250m to £500m.

The first vehicles used a new section of the A417 in July 2026, when the old A417 between the Air Balloon and the B4070 was closed permanently. Friday’s switch is the next step, not the last.

What it means for you

  • Driving to Cirencester, Oxford or the A40 from Stroud. The layout changes at 6am on Friday 18 September. Allow extra time on the first few journeys and follow the signs, not the sat nav.
  • Driving to Gloucester from Cheltenham or Oxford. There is no longer a direct route. Use the new A436 to Shab Hill junction, then the underpass to the northbound slip.
  • Travelling overnight this week. The A417 is shut in both directions between the A46 junction and the Air Balloon from 9pm to 6am on Monday 14, Tuesday 15, Wednesday 16 and Thursday 17 September. The A436 and A417 towards Burford Road are also shut on the Wednesday night.
  • Planning anything east of Stroud in late September. Cowcombe Hill, the A419 out of Chalford, closes day and night from 29 September to 9 October. Both eastern routes are affected inside a fortnight.
  • Questions about the scheme go to National Highways on 0300 123 5000. Every dated closure in the district is on our Stroud roadworks and travel page.

Sources