Plans for a £125m scheme to widen a bottleneck on the main road between London and Hastings in East Sussex have been released.
The Highways Agency has published details of the upgrade to the A21 between Tonbridge and Pembury in Kent, making a the road a dual carriageway.
The scheme aims to cut delays and increase safety.
About 40,000 vehicles use the stretch of the A21 every day which has led to increased congestion in recent years.
The improvements would provide better access to Tunbridge Wells and include a new flyover linking the A21 to local businesses and Pembury Hospital.
Construction of the road would begin in 2012 if the proposals are given the final go-ahead.
Much of the A21, which passes through Kent and East Sussex, is single carriageway.
Five Kent and Sussex MPs have campaigned for improvements to the A21, saying the work was vital to coastal regeneration around Hastings.
Plans for the scheme have gone on display and in libraries and local authority offices in Tonbridge, Tunbridge Wells and Pembury and have been published online.
A two-day exhibition will also be held at the Angel Centre in Tonbridge on 15 and 16 January.
A public consultation on the plans will end on 5 March 2010.