If you think a dual carriage is only a section of road with two lanes going in one direction read on. Motoring editor Andy Russell says you never stop learning as a driver.
As a driver you never stop learning, no matter how long it is since passing your test.
I was driving on the A17 between King's Lynn and Sutton Bridge, a road I know like the back of my hand but hadn't travelled for a while, and noticed new speed limits signs at some junctions where the single lane in each direction is separated by an island.
With it being a single-carriageway road, and nothing to say to the contrary, the speed limit in a car is 60mph so when I saw the first of these speed limit signs in the distance I expected it to say 50mph, or even 40mph, to slow traffic for the junction.
Once closer, I saw it is a 60mph sign and, after the junction, there is a national speed limit sign – the white circular sign with a black diagonal stripe – denoting it is a 60mph limit.
I was confused – the road's speed limit is 60mph, then you have a sign at these junctions with a central island to tell drivers to do no more than 60mph followed by one for the national speed limit – on this road a maximum of 60mph.
I checked with Norfolk County Council and learned that although most people are aware that the speed limit for dual carriageways is 70mph, many drivers think a dual carriageway is a section of road with two lanes going in one direction whereas, in fact, it is a stretch of road separated by an island.
Without the 60mph sign, cars and motorcycles could have briefly sped up to 70mph through those junctions, then slowed to 60mph again. So why was the speed limit at the junctions lowered to 60mph.
A county council spokesman said: 'A coroner's inquest in to a tragic road fatality, which occurred at the A17/C69 Station Road junction in October 2014, called in to question the clarity of the speed limit through the junction. Following close analysis of the section of road, it was proposed to change the limit to 60mph, and signage was put in place in November 2017 to make the limit clear to drivers.'
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