One of Norwich's urban explorers reveals what it was like to go inside some of the city's infamous underground mines and tunnels.
From the middle ages, through to the beginning of Second World War, Norwich was mined for chalk and flint and today many of the mines, believed to have been dug between the 12th and 18th centuries, still remain underneath the city.
The chalk and flint obtained from such mines was used to build some of the city walls as well as iconic buildings like the Guildhall.
No detailed maps of all the mines within the city boundary exist, and thus a lot of independent research and exploring has been undertaken in attempt to uncover the exact locations.
One such person that has tried his hand at this kind of research is Jack Wicks, a catering and hospitality agency worker from Old Catton, who says he became 'addicted' to finding the mines after learning about their existence in early 2015.
He said: 'I started a new job at a pub in Bishopgate and become friends with a colleague who has a strong interest in urban exploring and one day the topic of the chalk mines came up.
'From the word go I was hooked and addicted to finding these mines, it was like an obsession. After much researching and going to different locations around Norwich over a month or two, one night after work we finally found what we were looking for.'
The mine the pair discovered was located in the Bishopgate area and is thought to be one of the earliest dug out in the city, dating back to the 1100s.
Jack, 25, recalls being 'shocked' at what he discovered upon entering the mine for the first time. 'After months of looking for it, I didn't know what to expect,' he said. 'There were so many different routes you could take down there and it's very easy to get lost if you're not paying attention or if you don't take any rope. We did end up going very deep underground and spent about an hour down there before noticing we had started to go round in circles.'
Their first exploration left the pair determined to find more of the city's hidden tunnels, and shortly after they discovered the Harford Hills Chalk Mine in the south of the city, the entrance to which has since been closed off.
'This mine was a lot larger with the tunnels being wider and taller,' Jack said. 'We could tell it had been dug out a lot later than the first one due to the good condition it was in. I don't think this one was as deep as the Bishopgate area mine but most of our experiences were the same, just looking around an awesome place that's hidden away and stuck in time.'
Jack also managed to locate Thorpe Lodge tunnel in Thorpe. He suspects that there are many other tunnels hidden in the city that aren't related to chalk mining.
'I believe that there are a lot more tunnels underneath Norwich city centre that were used hundreds of years ago to get about the city, going from the castle to main points within the city at the time like Shire Hall and the Cathedral,' he said. 'I think the tunnels also led to quite a lot of different buildings around Norwich which now stand as pubs, shopping centres, even hairdressers'.
However after experiencing firsthand the dangers of the mines, he doesn't recommend that others risk trying to find the tunnels.
He said: 'I did experience a bit of shortness of breath while in the mines. Entering them is very dangerous and I would not advise anyone to go into them. Other than the obvious risk of it collapsing and trapping you inside, there can also be dangerous gases lurking around that we can't smell and you might not realise you are breathing them in.'
Norwich City Council also advise that the public refrain from seeking out the mines. They said: 'The majority of chalk mines in Norwich are blocked up and the remainder are inaccessible as they are on private land. Chalk mines are dangerous places because of the risk of collapse should you disturb anything and there can also be a lack of oxygen, so we would strongly advise people against entering them.'
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