If you have ever felt like you were stuck in gridlocked traffic in St Albans and going nowhere fast, it turns out you were not imagining it.

A study into data collected from 20 million miles of travel throughout Britain has shown that rush hour traffic has the biggest impact in the likes of St Albans.

Across Britain the typical rush hour slows traffic speed in urban centres by 3.6 miles per hour – an average delay on a 30 minute commute of about six minutes.

In St Albans the delay is about nine minutes, according to information released by insurance company Direct Line.

The figures were obtained by analysing data gleaned from telematics devices, GPS units which capture when and where a car is driven, also known as black box technology.

When it comes to rush hour hold-ups, St Albans motorists face greater delays than Brighton (5.10 minutes), Bath (7.13) and Worcester (8.58).

By contrast, Winchester drivers fare worse with an average 12.8 minute delay, while at the other end of the scale Edinburgh, Liverpool and York motorists are held up for less than four minutes.

The study shows that St Albans comes 15th out of 49 cities when it comes to the slowest average rush hour speeds, with motorists travelling at 12.95mph at peak times.

Westminster tops the list with 10.06mph while lucky Peterborough drivers can reach their destination faster, travelling at an average 19.25mph.

And while some locals might assume that the busiest day on St Albans’ roads would be Wednesday, market day, data shows that it is actually Thursday.

On the positive side, the city boasts a better off-peak average speed than many other centres, with motorists travelling at 18.39mph.

That is higher than in Canterbury (17.94mph), Cambridge (14.42mph) and Manchester (15.33mph).

Paul Felton, head of telematics at Direct Line, said: “This analysis shows the real experiences of motorists across the country on their commuting journeys.”