Nearly 10 tonnes of rubbish was cleared from the A41 in a clean-up operation in February which cost around £25,000.
During the blitz, two teams picked up litter from slip roads, junctions and grass verges as well as the central reservation along a 26-mile stretch of the road from the M25 junction to the boundary with Buckinghamshire.
The litter collected included general litter thrown from cars as well as car parts and even some road signs which had been knocked over.
The two-week tidy up was carried out by Dacorum Borough Council.
Craig Thorpe, environmental services group manager at the council, said: “This has been a huge and costly task as it involves applying and paying for a traffic management system so parts of the road can be closed during the operation.
“While clearing the central reservation, we worked with highways contractor Ringway and used its traffic management system but used our own traffic management system for the main road closures.
“The cost and time involved means we can only clear this road once a year so would urge drivers to keep the A41 as litter free as possible and take their rubbish home.”
Dacorum Borough Council has been raising awareness of the litter problems on the A41 through extra signs and more litter bins in lay-bys which are cleared twice a week.