Central London has the slowest rush-hour speed in the country, according to a survey.
Cars crawl through the city as slow as 10mph.
The average peak-period speed for motorists in Westminster is just 10.06mph, analysis by Direct Line Drive Plus found.
The fastest rush-hour rates were in Peterborough, with an average speed of 19.25mph, followed by York (17.64mph).
Overall, the typical rush-hour slows traffic speeds in urban centres by an average of 3.6mph.
Although not recording the lowest average rush-hour speed, Canterbury took the unwanted accolade of the city most affected by peak-period traffic, with the rush hour adding almost 10 minutes to a normal 30-minute journey.
The next most-affected cities were St Albans in Hertfordshire where rush-hour drivers were likely to be delayed for 8.9 minutes and Worcester (8.6 minutes).
After Westminster, the slowest rush-hour speeds were to be found in Lancaster (10.88mph), Cambridge (11.30 mph) and Hereford (11.49mph).
Among the quicker-moving rush-hour locations were Coventry, Chelmsford in Essex, Swansea, Stoke-on-Trent and Dundee.
Thursdays, rather than Mondays or Fridays, appeared to be the worst day for rush-hour congestion.
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