Archaeological work preceding a housing development revealed mid-Devensian (MIS 3) deposits preserved in a geological fault, a graben feature, on an interfluve plateau. Rare evidence for Early Upper Palaeolithic open-air occupation was characterised by a scant lithic signature of the Lincombian-Ranisian-Jerzmanowician (LRJ) leaf-point techno-complex of the North European plain. The lithics included a complete leaf-point, another broken example with traces of impact damage, and knapping debitage indicating leaf-point maintenance. The site also preserved good evidence for an open-air hyaena den with abundant faunal remains. Discrete bone clusters were present, some of which probably represent meat caches for hyaena cubs in the burrows and scrapes of a maternity den. It is suggested that the hominins targeted the den site to forage the stored food. Their occupation is associated with a group of spirally-fractured wild horse bones thought to be the result of marrow extraction by humans, and these have been dated to 44,290–42,440 calibrated years before present (44.3–42.5 kyr cal bp), comparable to the date range of continental LRJ sites. The early date of the LRJ techno-complex corresponds with that of the oldest Neanderthals in northern Europe, but possibly overlaps with the recently reported early dates for anatomically modern humans. However, it is concluded that the oldest Early Upper Palaeolithic technology in northern Europe was the product of final Neanderthals.