This Atlantis is the islands formed from the remnants of a lowland landscape, under which lie soft glacial deposits. In the course of their recent research, experts found two lost islands in Cardigan Bay on a medieval map. And they claim to have solved the mystery of the “Welsh Atlantis”, writes Express.

The islands were discovered by geographer Simon Haslett of Swansea University and his colleague David Willis of Oxford University. Professor Willis, who specializes in Celtic languages, drew attention to the Welsh literary tradition of a landscape called Cante’r Gwaelod, which is depicted in what is now Cardigan Bay, lost in the sea.
When two scientists consulted the oldest map of Great Britain, the Gough Map, which dates back to the late Middle Ages, they found that it marked two islands in the same location that do not exist today. collection of the Bodleian Library, Oxford, clearly shows two islands off the coast of Cardigan Bay—one between Aberystwyth and Aberdovey, and the other lying between the first island and Barmouth to the north.

It is not clear exactly when and by whom the Gough Map was created. The antiquarian Thomas Martin, who owned the map until his death in 1771, believed it to date from the reign of Edward III, i.e. between 1327 and 1377.

Research by scholars has suggested dates between 1355, when Coventry’s city wall was built, and 1366, when the town marked on the map as Sheppey was renamed Queenborough.

Based on the geology of the area, researchers believe that the islands are remnants of a lowland landscape underlain by soft glacial deposits. They were formed during the last ice age, which ended about 11,700 years ago. This soft, easily eroded landscape has been incised by rivers and truncated by the sea until only two islands remain. “We have every reason to believe that the coastline of Cardigan Bay once ran much further seaward, and the site of the mouth of the river Istite, indicated by the Roman cartographer Ptolemy, was approximately 12 km from its current location,” the experts emphasized.

As the smaller sediments broke down, larger components of gravel and boulders remained, the researchers explained. Accordingly, it is not surprising that the location of the islands on the map coincides with underwater accumulations of gravel and boulders known as chaff.

Gough’s map is remarkably accurate given the surveying tools then available. The islands are clearly marked and may corroborate contemporary reports of lost land mentioned in the Black Book of Carmarthen.