Harford Hills Chalk Mine
Norwich was mined for chalk and flints from the Middle Ages until the beginning of WWII but some of the chalk mines are much older, the earliest are believed to date from the 12th century. The oldest mines are located closest to the centre of Norwich and more mines were dug further out as the city grew. The chalk was used for liming in agriculture and in building mortar. The flints that can be seen embedded in layers in the chalk were used to build the city's walls and some of Norwich's finest buildings such as the Guildhall. The last chalk mine to close was at Harford Hills, to the south of Norwich. There are no detailed maps of all the mines located within the city boundary but it is known that the great majority were privately owned and dug between the 12th and 18th centuries, at times when record keeping was not thought necessary. The only existing records date from later times when the Council documented the locations where collapses have occurred that were deemed to be due to mine workings. (Much of this information was taken from the County Council's website.)
The site of this chalk quarry is now a woodland and has, over the years, been transformed into one of eight local nature reserves in Norwich - Danby Wood Nature Reserve. Situated on the southern fringe of the city, the banks, hills and hollows created by the quarrying activities are traversed by numerous tracks and paths that are enjoyed by many walkers. The woodland is adjoined by Eaton golf course in the west and there is a green - sporting two ancient tumuli - and a children's play area immediately to the north, separating the woodland from a housing estate beyond. Marston Marsh is located on its southern edge.
The entrance to the disused mine is off the beaten track and well concealed. It was sealed when the quarry closed but curious explorers have nevertheless managed to find a way inside. Here are two views of what appears to be the only entrance/exit to the mine - one looking into the mine, the other one looking towards the exit.
A word of caution: places like these should never be entered alone. They can, however, be explored by using common sense and taking a few precautions such as wearing sturdy boots and appropriate clothing. Bring along a good torch (and spare batteries, just in case), a compass, and by all means a map, provided there is one. Make sure that you always know exactly where you are. Take the quickest route out if you start feeling uncomfortable. Bear in mind that your mobile phone will be useless since there is no signal underground.
Fortunately, the labyrinth of tunnels in Harford Hills mine is well marked by a system of purple arrows that point in the direction of the exit, whereas crosses mark dead ends and filled in shafts with crawl-spaces that lead to no-where. Whether these marks were left by surveyors or by visitors I do not know.
Following the main tunnel that runs roughly from south-west to north-east from the entrance, a crawl-space soon branches off in the north wall. It links with a system of tunnels a short distance further to the north. Some of these eventually connect with passages leading to the heart of the mine - if one knows where one is going.
This is the crawl-space. It is large enough to comfortably crawl through. On the other side the ground drops sharply and two narrow passage ways can be seen around the corner. The one leading north-east terminates in a dead end. The one leading south-west has a turn-off running in northerly direction. It links with a tunnel further to the north-west, a short distance south of the geographical centre of the mine.
The main tunnel terminates in a dead end, where the walls still bear the soot marks of tallow candles, placed here by the workers to provide lighting. Evidence that there once used to be a shelf here can also be seen, alongside a few discarded rusty old pots on the floor.
A tunnel branches off, leading in southerly direction, roughly in the middle of the main shaft. It is accessed through a narrow passage and soon met by another, somewhat wider shaft that leads north-easterly. After making a slight curve it meets yet another tunnel running in north-southerly direction. We notice that the floor in this passage, like in the one that connects with it, consists of ancient clay. Also, there are no candle holders and soot marks on the walls - evidence that this tunnel was dug at a later time than the ones located further to the north-west, ie closer to the entrance/exit.
We walk past what at first sight appears to be a dead end. A closer inspection reveals that this section appears to have been filled in, or perhaps it has collapsed. There is ample room for an adult to crawl along here, on top of the debris. However, we decide against following this route. After having explored this passage from the other direction, we think that it is still possible to get through - to be verified, perhaps, on another day.
Instead, we are heading into the south-eastern corner of the old chalk mine. Passing from one tunnel to another via one of the small openings in the wall that we are by now quite used to seeing, we follow the shaft that runs from north to south, along the eastern edge of the mine. It is narrower than its neighbours and full of debris. About halfway along we reach what at first looks like a crossing of tunnels. However, after having established that all the passages here appear to narrow to crawl-spaces or turn into dead ends, we return the way we came from.
Having passed on the crawl-space and after having explored the tunnel branching off to the south and the system of passages adjoining it in the south-east, we return to the main shaft to follow a passage that branches off towards the end of it and leads to the north-east, running towards the north-eastern edge of the golf course above. We notice several sharp drops on our way, knowing that as we proceed it links with another shaft that will eventually take us right into the heart of the mine. Artefacts such as old cooking pots and a beer bottle (the latter left by a recent visitor) can be seen along the way. We find more soot marks on the walls here, black discolourations immediately above small protuberances that jut from the tunnel's walls, with traces of wax still evident.
A wall of chalk awaits towards the end of the tunnel, too high to clamber up on in order to investigate this dead end. In front of this wall another tunnel, running from north-west to south-east, crosses.
Turning in south-easterly direction from these crossroads, we pass through a narrow opening into the tunnel on the other side. It leads to a longer shaft that runs from north to south, connecting with the main shaft via another tunnel running in westerly direction. The tunnel floor here is soft and springy and we discover that it is ancient clay that would once have formed the sea bed. It is drying out and has developed cracks. The clay reaches up the tunnel walls to a height of about 60 centimetres. We also notice that there are no candle holders and soot marks on the walls in this and the connecting tunnel. From this we gather that these tunnels must have been made later when battery-powered lamps were available to the workers.
Followed in the opposite direction, this passage links with a shaft that runs from north to south. The map shows that further to the south this tunnel connects with a another that, after some twists and turns, eventually leads back to the main tunnel and to the entrance/exit from there.
Here we are following a flight of narrow tunnels that lead west, where, via a short passage curving north-westerly, we soon reach a shaft running from north-east to south-west. We are still heading continuously downwards and have now reached the shaft which somewhat further to the north-west links with another that leads even deeper into the the mine, now in south-westerly direction. The tunnels have become progressively narrower the further down we have gone. The air is getting stale and we can see our breath evaporating in the light of our torches. It is cool and damp in this dark and confined space. Were it not for our map and the arrows on the wall pointing the way, we would probably by now be a tad confused as to which way to continue, with all these tunnels and passages branching off in every direction, or so it seems, all looking more or less the same.
We have reached the tunnel that leads to what appears to be the geographical centre of the mine. The map shows a particularly confusing warren comprised of short narrow tunnels, passage ways, dead ends, and holes in the walls, some of which linking with other tunnels, others leading to no-where. We are still walking steadily downhill, the shafts are narrow.
It is at the end of this tunnel, which, judging by the map is situated roughly at the geographical centre of the mine, and probably at its lowest point, that we discover a stone wall. It is adorned by a number of initials, written in chalk on the stones that here form part of the tunnel's wall. Some of these inscriptions appear to have been made by surveyors who had been here doing their jobs. Others seem to have been written by people who might well have worked in the mine before it was closed in around 1930. There are also inscriptions dating from the 1950s and later that can only have been left by curious visitors who had ventured that far down to explore. More inscriptions in other parts of the mine were applied by spray-painting, the most recent ones dating from 2011. Some of these are so small and unobtrusive that one has to look closely in order to see them.
The lens of my camera has fogged up and the air has become markedly stale. We have identified and are looking into the darkness of the tunnel that from here branches off in south-westerly direction. Following a zig-zag course, it leads first south-west, then north-west and eventually in westerly direction, where it terminates at a dead end somewhere below the western slopes of Eaton golf course. We are not keen on ending up there.
At this point we find that there are a number of turn-offs in close succession. Thanks to the excellent map we are using (it is depicted below) we know exactly where we are, however, I am no longer certain where I am going. We know that one of the passages here links with the main shaft that is only a short distance away. It is shown on the map, but we are not certain as to which one of the passage ways we are looking at it actually is. To be on the safe side, we decide to go back the way we came in, following the arrows, walking upwards to the exit and to fresh air.
There are still a number of tunnels, passage ways, dead ends, loops and crawl spaces to explore - on another day.
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From 1940 to 1944, part of this mine was used as an operational base by a patrol of Churchill's Secret Army, the Auxiliary Units. For more information about Eaton Patrol see Link
Recently, this 90+ percent accurate map of the Harford Hills chalk mines was produced and published by Chris Richmond on his website 'Norfolk Uncovered'. The map is reproduced here by his kind permission.