The A45 in Coventry has been named as one of the most improved roads in the country for safety.
According to a new AA survey the number of serious accidents has been halved since the installation of speed cameras and gaps in the central reservation were removed.
Ina previous report, the stretch between the city centre and junction six of the M42 was highlighted as one of the most dangerous in the country after 71 fatal or serious accidents between 1997 and 2001.
The new survey, compiled by several motoring organisations including the AA Motoring Trust, lists 370 of Britain's worst A roads.
It says hundreds of rural roads are badly designed, poorly maintained and exceptionally dangerous.
Simon Woodings from the AA says: "Clearer road markings, speed cameras, improvements to junctions and the addition of cycle lanes have meant a drop of 50% in accidents on the A45.
"There are certain costs to introduce some measures - the average speed camera costs between £10,000 and £15,000, whereas new road markings are cheaper.
"But when you think the average cost of a fatal accident can reach up to £1m because of a police investigation, a potential court case and insurance these new measures are worthwhile."
Lives saved
Of the 370 roads included in the list, 13 have been pinpointed as having improved.
Mr Woodings added that lives have now been saved because of the safety upgrades.
"Twenty lives have been saved on these 13 roads and 180 serious accidents have now been avoided.
"We hope that the remaining roads are improved as soon as possible."
Other regional roads the AA say are dangerous are the A44 from Leominster to Worcester, the A53 from Leek to Buxton and the A5 from Daventry to Rugby.