Revised plans have been unveiled to improve a notorious accident blackspot in The Cotswolds.
The A417 between Gloucester and Swindon has regularly become congested at the Air Balloon Roundabout near Birdlip.
Proposals for a £435m dual-carriageway were delayed in July following a consultation, after the National Trust said it was concerned about the loss of ancient woodland.
Highways England has launched a consultation into its updated designs.
The only stretch of the existing road to not already be dual carriageway has been known locally as "the missing link" 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.
Changes to the original designs have included new crossings for the Cotswold Way and Gloucestershire Way footpaths and a change in gradient of the road where it would climb an escarpment near Crickley Hill.
Other differences include a new design for the Cowley junction and the proposed rerouting of the B4070 to Birdlip via Barrow Wake.
Highways England said there would also be improvements for walkers, cyclists and horse riders, including disabled users.
Michael Goddard, Highways England's senior project manager for the scheme, said the proposals would "benefit local connectivity, accessibility and reduce the scheme's impact on communities, the environment, and the local landscape".
In a joint statement, Cotswolds Conservation Board, Gloucestershire Wildlife Trust and the National Trust said the proposed changes had "the potential to improve the scheme", but they said there were "still areas of concern".
They said they were concerned about "the functionality and design" of some of the crossings,
"The three overbridges must deliver their intended outcomes - connecting habitats via wildlife corridors and counteracting the negative impacts of the new dual carriageway on protected wildlife sites," the statement said.
"The crossings and overbridges should also be visually in tune with the special characteristics of the Cotswolds landscape."
They said there were also concerns about the impact on Sites of Special Scientific Interest.
The public consultation is due to end on 12 November.