The travertine of San Quintín de Mediona (province Barcelona) offers a rich ensemble of stone-age sites.  Between 1987 and 1997 several shelters were excavated and Middle Palaeolithic occupations were brought to light at Mediona I, La Canyada, Can Costella and La Boria.  

The oldest Middle Palaeolithic occupations of the San Quintín de Mediona Valley are dated between 90.000 and 80.000 BP. At this point in time the large travertine-dams had eroded and small cavities and shelters formed at the flanks of the valley. Fans accumulated in front of the shelters and were inhabited by middle palaeolithic people. They had direct access to the river or small ponds. At Can Costella an occupation is dated to the final phase of the oxygen isotope stage 5.

Mediona I provides a long succession of at least seven occupation horizons. The succession starts in oxygen isotope stage 5 and goes up to stage 4, maybe even longer. Loess clay in the overlaying stratum supports a late date of the uppermost horizon, pointing to a cold climate. Besides stone tools and kill-remains the excavation unearthed hearths and other settlement structures. ESR-dating of burned flint produced an age determination of the lowermost occupation between 84.000 and 62.000 years ago. By contrast, the time of occupation at La Boria remains uncertain. At this site the interrelation between human occupation and the formation of travertine becomes most clear. The occupation took place on travertinsand of previous basins and most probably close to stagnant water.

From about 40.000 BP, the valley was affected again by major erosion, lowering the bottom of the valley by 15 meters. At that time, at the latest, the existence of settlements can no longer be proven. Only from the Holocene onwards archaeological material provides evidence again for human occupation in the valley.

The investigations were accomplished in collaboration with the Universitat Autònoma de Barcelona, Archaeobiology at the University Tübingen, the Institut für Geographie und Geoökologie der Universität Karlsruhe as well as the DAI Madrid. The project was financially supported be the German Research Foundation. The evaluation of the excavation is still in progress.