Heres how it happened
A brief history of speed limits Between 1865 and 1896 locomotives on the highway had to be preceded by a pedestrian carrying a red flag and were subject to a speed limit of 2mph in cities, towns and villages and 4mph elsewhere
On 28 January 1896, Walter Arnold of East Peckham, Kent became the first person in Great Britain to be successfully charged with speeding. Travelling at approximately 8 mph, he had exceeded the 2 mph speed limit for towns. Fined 1 shilling (5p) plus costs, Arnold had been caught by a policeman who had given chase on a bicycle so began one of the most lucrative ways of making money by Local Authorities and the Exchequer
The maximum speed limit was then increased to 14mph and again, in 1903, to 20mph.
In 1930 speed limits for cars and motorcycles were abolished.
In 1934 a general 30mph speed limit was imposed on roads in built up areas (effectively roads with street lighting) which remains to this day. Other roads had no speed limits at all.
It was not until 1965 that a national upper limit of 70mph was introduced for all roads, including motorways. Since 1977 the speed limit for cars and motorcycles on dual carriageways has been 70mph, with a 60mph speed limit on single carriageways. In 1999 local authorities were given the powers to introduce a 20mph speed limit without requiring the consent of the Secretary of State. Speed Limits are not only governed by the type of road you drive on but the type of vehicle you are driving on that road it is the drivers responsibility to know the limits applied to his vehicle at all times