Some of the most dangerous parts of the A1 in Lincolnshire are to undergo more than �2m worth of improvements. Safety measures will include a ban on U-turns.
Eight gaps in the central reservation will be closed in the project, between Long Bennington and Gonerby Moor near Grantham.
U-turn bans will be applied to a further seven gaps on the same stretch.
A new link road is planned between Foston and Long Bennington, and lane layouts will be upgraded.
The Secretary of State has decided the scheme should go ahead without a public inquiry.
Work is due to start in October and finish in August next year.