It's 40 years since postcodes were rolled-out across the UK to make letter-sorting easier.
Norwich pioneered the idea and, to mark its role, has been issued with a blue plaque for the city centre by Royal Mail.
There are now 1.8 million postcodes covering 29 million addresses across the country.
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Remaining dry with warm sunny spells on Monday.
Douglas Carswell told ITV's Peston On Sunday he wanted to "support" the government as a "critical friend" but refused to rule out a return.
The Ukip leader confirmed he had "no prior warning" of Douglas Carswell's resignation from the party as he hit out at the "staunch Tory".