Half of all fatal road crashes in the UK occur on 10 per cent of Britain's roads, a report from the Road Safety Foundation has revealed.
The report - Saving Lives for Less - covered 28,000 miles of A-roads and motorways in the UK, and revealed Scotland to have the highest-risk highways on average, followed by northern England.
The A357 between Macclesfield and Buxton was identified in the report as the most dangerous road in the UK.
The Road Safety Foundation suggests that, by investing small sums of money in making accident blackspots safer, the high cost of emergency services and hospitals could be reduced.
The A40 between Llandovery and Carmarthen was identified as the most improved road, where improved junctions and markings, combined with new high friction, anti-skid surfaces saw the number of serious accidents fall from 27 to just seven from 2005 to 2008.
The West Midlands was identified as the safest region, while the report noted that the number of fatal crashes had decreased by five per cent in the last three years.