A major project lasting six months has started on the road between Pinchbeck and Spalding.
The scheme will create new facilities for people walking, wheeling or cycling between Kings Road and Enterprise Way.
There will also be a significant upgrade to the road, traffic signals and street lighting along the route.
Work on the site’s compound started this week.
Coun Ingrid Sheard, representing Spalding Elloe on the county authority, said: “This is a really positive investment for both Spalding and Pinchbeck, and I’m delighted to see construction beginning.”
The scheme will use around 5,700 tonnes of road-building materials throughout the works.
A combination of road closures, temporary signals and one-way traffic will be used as required.
“As well as improving road safety, the scheme will support healthier lifestyles,” added Coun Sheard.