La Cotte

La Cotte is a headland on the north-western coast of Jersey that contains one of the most important geological and archaeological sites in the British Isles, with an ancient beach platform cut into the granite that dates to the last interglacial period approximately 125,000 years ago, a time when sea levels were higher and the climate was warmer than at any point in the subsequent Pleistocene epoch. The platform is exceptionally well-preserved and represents one of the most significant fossil and archaeological sites in the Channel Islands, with a fossil record that has contributed significantly to understanding of the environmental history of this period.

The beach platform at La Cotte is carved directly into the granite of the headland and extends across a considerable area of the foreshore, and the ancient shoreline is clearly visible in the form of wave-cut notches and marine erosion features that were formed when sea levels were higher during the last interglacial period. The platform is exposed at low tide and the ancient beach deposits that overlie it are accessible for study, though the site is not generally open to the public for visiting. The geological significance of the site lies in the exceptional preservation of the interglacial deposits and the clarity of the stratigraphic sequence.

The cave system at La Cotte is associated with the beach platform and contains the richest fossil deposits at the site, with a sequence of accumulated sediments that has been built up over many thousands of years and which contains the fossilised remains of a rich fauna including mammoth, woolly rhinoceros, horse, red deer and a range of smaller mammal species. The fossil assemblage from La Cotte is one of the most important from the Pleistocene period in the Channel Islands and represents a diverse community of mammals that inhabited the region during a warm phase of the glacial cycle, providing a sharp contrast to the cold-adapted fauna that characterised the glacial periods.

The stratigraphy of La Cotte is complex and represents multiple phases of beach and slope deposit accumulation separated by periods of erosion and soil formation, and the sequence of deposits has been studied by geologists and archaeologists for over a century with the most significant excavations taking place in the early twentieth century. The complexity of the stratigraphy reflects the changing sea levels and climatic conditions of the Pleistocene period, and the site provides a detailed record of environmental change in this part of the Channel Islands over a period of approximately 100,000 years.

The fossil assemblage from La Cotte is substantially documented and is largely held in the collections of the Jersey Museum, where it represents one of the most significant Pleistocene collections in the Channel Islands and provides an important resource for ongoing research into the environmental history of the region. The fossils document a time when the climate was warmer and sea levels were higher than today, and the Channel Islands formed part of a continuous landmass connecting Britain to France across what is now the English Channel, which was either dry land or a freshwater lake during the glacial periods.

The La Cotte fossils are particularly significant because they represent an interglacial period in the environmental history of the British Isles, a time when hippos and elephants were living as far north as what is now England, and the Channel Islands served as refugia for these species during the repeated glacial cycles that characterised the Pleistocene epoch. The study of the La Cotte fossils contributes to understanding of how species adapted to island environments and to climate change, and ongoing research at the site using new excavation techniques and dating methods continues to provide new insights into the environmental history of the region.

La Cotte contains one of the most important interglacial fossil sites in the British Isles, with an ancient beach platform dating to approximately 125,000 years ago and a rich fauna including mammoth, woolly rhinoceros and horse.

The stratigraphic sequence at the site spans multiple phases of the Pleistocene period, providing an exceptional record of environmental change in the Channel Islands.

The site is a geological Site of Special Scientific Interest and the fossil collections are held at the Jersey Museum, representing a major resource for ongoing research into the environmental history of the region.