A new safety scheme has been installed on the A52 in Lincolnshire to try cut its high accident record.
New special passing bays, which resemble mini lay-bys, have been built as part of the project.
They will allow slow-moving vehicles like tractors and other farm machinery to pull-over so long tailbacks of traffic behind them can get past.
In the last five years there have been 30 fatal and 154 serious injury collisions on the road.
The 33km (20.5 mile) A52 is one of the East Midland's busiest and most dangerous roads, with over-taking a factor in many accidents.
Thirteen bays have been installed from Friskney to Skegness, with more expected on the Boston to Friskney stretch at a later date.