Most of the information contained on this page comes from the notes made by F. N. Cambell James, as published in "The Submerged Forest at Both and Ynys-las, Cardiganshire
Data for the Study of Post-Galacial History no.1" by H. Godwin & L. Newton, 1938.
The location of Borth's submerged forest is a well known secret. It stretches intermittently for two to three miles along the shore between Ynys-las and Borth and lies about half-way between high and low water. What makes it a secret is that it is normally hidden under a layer of sand and is only exposed under certain circumstances.
On the rare occasions when it is fully exposed a flattened expanse of peat containing the remains of numerous prostrate trees is revealed. Pine (Pinus), alder (Alnus), oak (Quercus) and Birch (Betula) have all been identified. The root systems of the larger trees are generally spread horizontally, though some also grow downwards. This is typical of trees growing in fen woods where the high-water table keeps all the tree roots with the exception of alder in the aerated surface layers of the peat.
Pollen has been analysed from various depths which appears to show a sequence of development typical of the succession from reed bed to raised sphagnum bog but which had been interupted at the fen woodland stage.
Because the upper layers of peat have been lost to wave activity there is no evidence to indicate what events have caused the forest to become submerged but radio carbon dating suggests that the trees died between 4,500 and 6,000 years ago. The long sequence of development of the submerged forest peat indicates a long period of freedom from the marine influence under which the underlying clay was deposited.