Have you ever wandered through the city and noticed a number of large Hs marked on the outside of some buildings?
We delved into the past to find out what they are and why they are there.
The symbols, which may seem strange, actually stand for 'hydrant'.
They were painted on buildings at the outset of the Second World War, in anticipation of the German Luftwaffe carrying out bombing raids on the county.
The symbols marked the location of water hydrants, so they could be easily found by firemen called to fight blazes caused by bombs.
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The Hs were painted in large white font so that they could be seen more easily in low-light conditions, such as during blackouts.
They were used to great effect during the Baedeker raids of 1942 which saw the city extensively targeted by the Luftwaffe.
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More than 200 civilians were killed and thousands more injured during these raids.
As well as the 'H' signs, similar ones were used to mark air raid shelters ('S') and emergency water supplies ('EWS').
None of these are known to survive in Norfolk, but they can still be seen in London.
It is unclear how many of the hydrant symbols there were originally in Norwich.
Some of those surviving ones are still found near modern hydrants and can be seen next to modern hydrant markers, in bright yellow.
These Hs can still be seen in King Street, Wensum Street, Saint George's Street, Colegate, and Muspole Street - having survived for more than 80 years.
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