A plan to improve a notorious accident blackspot on a route which links two motorways has been announced.
There have been a number of fatal crashes where the A417 near Gloucester becomes a single lane, which has led to repeated calls from campaigners for a new road to be built.
Highways England has now chosen a preferred route for a new dual carriageway.
The new 3.4 mile (5.5km) road will cost £435m to build.
The A417 runs between Gloucester, Cirencester and Swindon and is used by many motorists travelling between London and the West Midlands as a shortcut between the M4 and the M5.
The existing road bottlenecks at the Air Balloon roundabout near Birdlip, and has previously been described as one of the "worst pinch-points" on the national road network.
In 2014, it was reported there had been 340 casualties on the road in 15 years.
Another option was also considered following a public consultation, but it was ruled out as it was on a steep hill with a sharp bend so speed limits were needed.
Senior project manager Michael Goddard said the scheme would bring "a number of benefits to the area".
He said: "Besides making journey times more reliable, reducing rat-running through neighbouring communities, it will also improve the lives of people who live close to the route and make it easier for drivers, walkers and other local road users to get around."
The new road will have a 70mph speed limit and short road connecting Birdlip to the A417.
Road crossings for pedestrians and cyclists will be included and the Air Balloon and Cowley roundabouts will be removed.
The next step of the project will involve more detailed design work and further public consultation before a formal planning application is submitted.