Mesolithic nomadic hunter-gatherers set up specialized hunting camps on this river bank on several occasions. They left behind knapped flint artefacts and bone fragments of the animals they probably ate on site. These remnants, along with a hearth, suggest that these were temporary camps occupied for a few days to several weeks.
The hunter-gatherers used flint scrapers and flakes at this site for butchery and to scrape skin to make clothing or hut coverings, but the abundant flint waste show that their main activity was increasing their supply of arrowheads. They used resin to haft these minuscule points with geometric forms, characteristic of this period, to wooden arrow shafts.
While most of these tools were made from flint nodules found in the alluvial deposits of the Seine, sandstone from the Tertiary outcrops at Meudon or Clamart were also brought to the site in the form of blocks or preforms to produce prismatic tools. Though the precise function of these tools is unknown, they could be related to the production of flint arrowheads or their wooden shafts.

In a temperate zone where forests replaced glacial steppes, and red deer and wild boar succeeded reindeer and mammoths, the bow and arrow, which appeared around 12,000 years ago, was the preferred weapon of Mesolithic hunters. And it is during this period that lithic tools became progressively microlithic.