Something is hiding beneath the waters of Stithians Lake. And at certain times of the year, when the level drops low enough, these wonderful artefacts, carved more than 4000 years ago, reveal themselves.
When Stithians Dam was completed in 1967 the shallow valley behind it was completely flooded. Nearly 300 acres of farmland and three houses disappeared beneath the steady creep of the rising waters. But, unbeknownst to us, something far older and far more mysterious was already hiding in that valley. And ironically it would be the flood water that was eventually going to reveal this forgotten treasure more than 20 years later.
Sunken Treasure
The summer of 1984 was one of the driest in living memory. So little rain fell that year that the level of the man-made Stithians Lake dropped to an unprecedented low. As luck or fate would have it an experienced field-walker and member of the Cornwall Archaeological Unit, Don Cave, happened to be walking the shore of the reduced reservoir and he noted something unusual. A number of cup-marked stones. He also discovered a large quantity of worked flint and a fragment of a greenstone axe close to the stones. Mr Cave reported his finds to the CAU office.

The foreshore of Stithians Lake
It soon became clear that Cave was not the first to have spotted the stones. They had been reported by local walkers in 1980 and then again in 1982. On both occasions however the water level had risen again before they could be inspected. This time Mr Cave was able to lead the members of the CAU to the stones. In August 1984, before the site could be inundated, the CAU surveyed and photographed the area. The team also completed a walk of the entire foreshore of the lake which resulted in a large collection of flint finds.
I read about the stones for the first time while researching something else. I had never heard of them before and got pretty excited. So as this summer (2019) had also been reasonable dry I decided to take a look for myself. I really didn’t have high hopes of finding them. I only had vague information as to their location on the side of a lake that is several miles around. And of course I had no idea whether the water was actually low enough to reveal them.

Re-discovering the Stones
Water has played an important role in the story of these precious stones. Although at first it seems frustrating that such a fascinating part of our Cornish history has been accidentally hidden from us, in fact it is the opposite. Without the flooding of this valley it seems probable that we may never have known that these magical stones existed. They are located in a small field which at the time that the valley was flooded was the only one in the area that had never been cultivated. It was considered too stony to warrant the effort required to clear it. The cup-marked stones lay buried beneath a layer of top soil and scrubby vegetation. Miraculously it was the steady action of the flood water that gradually, slowly peeled away that mask of dirt.
As I walked along the foreshore this August my mind was drifting to other things. The sound of the water lapping, the various birds flitting about, the silent drowned houses beneath the little splish-splashing waves. Then quite suddenly the sun popped out from behind a cloud flooding my surroundings in harsh light. And there they were, right at my feet. And I was so surprised to be actually seeing them!

These first stones I found are known rather unromantically as Group A. This group consists of 3 stones, although the largest is broken into 3 separate pieces. This huge flat stone was the one that had caught my eye and has roughly 48 cup-marks dotted across its surface. Of all the stones this is perhaps the only one where the marks appear to not be entirely random. You can make out what appears to be sickle-like half-moons of holes, and straight lines too. The stone is beautiful. Magical. I stood and gawped (with a massive grin on my face) for a good ten minutes before starting the hunt for the others.

I didn’t need to look far. Close by are another two stones, much smaller, known in a CAU report by Steve Hartgroves published in 1987, as Stone 4 and Stone 5. Stone 5 is strange in that with its regular shape and relatively flat surface it provides what appears to be an ideal canvas, yet the marks are confined to one edge of the stone.

There are two further groups of stones known as Groups B and C. Group B is about 100m further along the shore from the first group and has five stones which appear to be completely random in shape, size and design. Group C consists of two more stones, although I only managed to identify one.
During the study by the CAU none of the stones were lifted so we can’t know whether there are any further marks on their reverse. Indeed we can’t know whether any of the hundreds of other stones that litter the area is hiding a secret we just can’t see.

I spent a very happy couple of hours hunting down and photographing the stones before returning again later in the afternoon with my 81 year old father in tow! He wanted to see them too and managed to walk with me with the aid of his stick.
Surprisingly there are many more examples of cup-marked stones in Cornwall than you would think. The CAU lists a total of 34 known sites ranging from simple hedge stones to the impressive stone found at Tregiffian barrow. But their purpose remains a complete mystery.

The cup-marks at the Stithians site are similar to those found at Tregiffian, although they appear to be shallower perhaps due to the action of the water. This kind of decoration, if it is decoration, is more primitive in style than similar markings found in other parts of the country. Steve Hartgrove concludes:
“The fact that there is no recorded occurrence of ring markings or other more exotic motifs in association with the cups . . . suggests that the later Neolithic or Bronze Age inhabitants of the south-west peninsula were pursuing, in a rather unspectacular way (when compared to more northerly areas of Britain) their own traditions in respect of this branch of ‘rock-art’.”
This kind of decorative stone is often associated with burial sites. It is possible that the cup-marked stones at Stithians were incorporated into barrows in a similar way to the one found at Tregiffian. No definitive sign of any barrows or cairns has been identified here however, so this is purely speculation. It is entirely possible that they served some ritual purpose that is now lost to us. There are things going on here that we just can’t understand.



It sometimes seems like mid Cornwall has little to offer in terms of ancient monuments but I often wonder if that is just because so much of it has been swept away by the tide of industry that covered this area.
When you consider that within just a matter of a few miles of the cup-marked stones you can find Carwynnen Quoit, the Hangman’s Barrow, two (now-broken) stone circles, iron age settlements, an Neolithic axe factory and standing stones it becomes clear that there is more hiding in this landscape than is obvious at first glance.

Final Thoughts
There have been various attempts to identify what these cup marks might mean, what they were for. Beyond decorative designs there are some unsatisfactory (for me) theories that they were sockets (for what?) or mortar stones like the one found in Poldark mine carpark a few miles away, that they were the ‘doodling’ of quarrymen or just simply natural. I will always believe however that these cup marks served some kind of ritual purpose, whether they were tracking the passage of time or recording something of significance for their community, they do not feel utilitarian.
I would suggest, quite obviously, that the only way to discover more about this particular site and others like it, is through further study. And as I stand watching the waters lap ever closer to the cup-marked stones at Stithians I can’t help but wonder when I will see them again, and what other secrets are hiding beneath these waters.
My curious mind boggles!
I provide all the content on this blog completely FREE, no subscription fee. If however you enjoy my work and would like to contribute something towards helping me keep researching and writing about Cornwall’s amazing history and places you can donate below. Thank you!
Further Reading:
The Trenear Mortar Stone – Treasure in a car park!
I provide all the content on this blog completely FREE, there's no subscription fee. If however you enjoy my work and would like to contribute something towards helping me keep researching Cornwall's amazing history and then sharing it with you then you can DONATE BELOW. Thank you!
How lovely that your father got to see this too.
He was very excited to see them, kept saying, ‘well i never knew that’ and ‘i wonder if I’ll be around to see them again’ 😊😆
So interesting!! I must go to Stithians next time we’re down in Cornwall, hopefully will see these intriguing stones for myself. Really enjoyed this, thanks 😊
Totally fascinating. Thanks for another well researched bit of Cornish history.
That’s fascinating! How nice that both you and your father were able to see them. What a delight to know that they’ll just be hiding there in the water, waiting to be seen again some day. So special!
Lovely, I have been today, the lake is very very low,but I missed these, I have many images of the trees and farm normally under the waters, plus a small bridge and what looks like a septic pit once used.