Oldest evidence of Acheulean occupation in the Upper Seine valley (France) from an MIS 11 tufa at La Celle

The tufa deposit of La Celle, located in the Upper Seine valley (Northern France), has been known for more than a century and extensive collections of shells and leaf impressions exist. These fossils led earlier authors to recognize the tufa as evidence of an old temperate phase of the Pleistocene. New studies have recently been undertaken at the site in order to reappraise its palaeontological potential and to improve its dating. Recent investigations are based on the analysis of a new series of stratified samples, coupled with a revision of material in several old collections. The new work shows that the tufa accumulated under interglacial conditions and demonstrates the progressive development of forest biotopes culminating in the climatic optimum. In the upper levels the reopening of the landscape is registered by both molluscan communities and plant remains. The tufa at La Celle has been correlated with MIS 11, based on the geomorphological context of the site, together with the occurrence of ‘the Lyrodiscus fauna’, a malacological assemblage characteristic of tufa deposits of this period in Northwest Europe. This correlation is supported by radiometric measurements (U-series and ESR/U-series,) which have produced a mean age of ∼400 ka. Mammalian remains are also preserved and include Macaca and Hippopotamus, which are the first well-provenanced records of these species from this region. An archaeological horizon with flint artefacts demonstrates human occupation during the interglacial optimum. Analysis of the lithic artefacts confirms their similarity with the Acheulean assemblage collected at the end of the 19th century. La Celle therefore represents one of the best dated Acheulean occupation sites in Northern France and one where the palaeoenvironmental context can be described in great detail.