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Cantre’r Gwaelod

2 March 2014

At http://news.nationalgeographic.com/news/2014/02/140226-wales-borth-bronz… … is about the petrified trees of Borth, and asks if they are linked to the legendary kingdom of Cantre'r Gwaelod. I can therefore be described as a piece of speculation – but in this instance there is undoubtedly a grain of truth. The remains are said to date back 6000 years ago – yet, in the same headline they are said to be from the Bronze Age (between 4000 and 3000 years ago). Recent storms uncovered the huge forest off shore from Borth, the stumps of hundreds of trees. This is actually a well known phenomenon around the coasts of Britain and Ireland and mostly it reflects inroads by the sea as a result of rising sea level. Another forest was uncovered in Suffolk and another off Cornwall, and over the years this has happened on countless recorded occasions (and presumably on even more unrecorded occasions). In a way it reflects the drowning of the continental shelf around Britain and Ireland – including the drowning of the North Sea basin.

The forest visible now will be buried in due course by shifting sand brought in by the tides – but at Borth one thing will be missing. The tree stumps were buried in a thick peat layer – and this peat has to a large degree been washed out of the roots. What this means is that the original forest became a peat bog – and only later did it become submerged under the sea. The peat preserved the wood and the stumps. The real story then is that the peat bog did not disappear beneath the waves until the Bronze Age (or possibly even later) while the original forest was destroyed much earlier – five to six thousand years ago. It would therefore be interesting to know how the forest became just stumps of its former status. Was it destroyed by a blast (exploding bolide) and is there any evidence of tree trunks felled and pointing in a single orientation. Or was the forest destroyed in a landscape fire, leaving behind just the stumps (and in both instances a peat bog developing where the forest formerly stood).

The peat bog was said to have had a timber and scrub walk-way, and these are often found in bogs in Ireland and in Britain (in the Somerset Levels for example). There is a lot of literature on these constructs so I will not go over why they were built – only that they reflect a very wet environment (which in this instance, succeeded the forest landscape and hindered the growth of new trees). In other words, the loss of land in what is now Cardigan Bay occurred long after 6000 years ago and the manner it was lost could well have entered into the lore of the local people. Cantre'r Gwaelod was the Lowland Hundred (which by its name implies a large tract of the Bay). It is mentioned in old Welsh manuscripts, such as the Black Book of Carmarthen, a medieval copy probably with an origin in a monastery (rewriting old legendary material). The loss of land in Cardigan Bay and along the coast of North Wales and Merseyside is an ongoing affair – and still happens when sea defences are not maintained. 

Anyone who wants to get to know a little more about this subject should try and get hold of Nigel Pennick's book, 'Lost Cities and Sunken Lands' (Capall Bann:1997). He describes Cantre'r Gwaelod as disappearing as late as the 6th century AD (which may only mean there were further inroads at that time), at the beginning of the Christian era (assuming this was why the legend was written down, the proliferation of monasteries). He says on page 72, 'for centuries storms have been turning up the remains of inundated forests along that part of the Welsh coast. Giraldus Cambrensis claimed that St David's Head, for example, formerly extended much further into the sea …'.  It was not until the 19th century that science caught up with the phenomenon. In 1832 the Reverend James Yates read a paper before Geological Society in London, 'A Notice of a submarine forest in Cardigan Bay'. The forest is described as extensive and split into tow by the estuary of the Dovey River. On the land side it is bounded by a sandy beach and a wall of shingles. Yates also claimed some of the stumps belong to Scots Pine trees, a species that was once endemic in Britain during the early to mid Holocene but that was pushed north by the Mid Holocene Warm Period (replaced by temperate forest trees). Scots Pines survived in Scotland and some parts of upland North Wales, only a matter of miles away from Cardigan Bay. This may indicate the forest was actually destroyed somewhat earlier than six thousand years ago. Most of the Scots Pines found in England today were planted in the 17th and 18th centuries as an exotic species on great estates (and have since self seeded) or were used as wayside markers by farms advertising they had lodgings and victuals available for travellers. Scots Pines are distinctive and can be seen from a great distance, especially in high isolated locations. Hence, it is recognised by landscape environmentalists that most Scots Pines in England are a recent arrival – and purposely planted.

The Journal of the Geological Society in London, in the 19th century, published more articles on submerged forests and Clement Reid became an authority on the subject (you can put his name in a search engine) and he claimed  that the forest land surface represents true forest growth extent above what had been the highest tide. He calculated the land must therefore have subsided by 55 feet – or the sea level had risen by that amount. This is going back 6000 years, possibly as much as 8000 years ago. Further evidence for such a massive rise in sea level has been noted in many other places, including the sunken valley off the coast of Cornwall and evidence of a forest covering most of the floor of the Bristol Channel (and Bouldnor Cliff in the Solent). At Chepstow the former rock bed of the River Wye was found 42 feet below low water mark (and so on).

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