9500 years of Rhône floods recorded in Lake Bourget: a comparison in the alpine chrono-climatic context Two sediment cores were taken from the deep northern basin of Lake Bourget in 2001 and 2004. The length of these cores was 9 and 13.5 m, whereas the depth of sampling was 130 and 100 m below lake-level, respectively. Dating by 6 and 19 14C dates showed they cover the last 7200 and 11 500 years, respectively. In the longer core (LDB 04-I) gravity reworking events make it difficult to interpret the palaeoenvironmental data prior to 9500 cal. BP. However, the high resolution measurement of the terrigenous contribution to lake sedimentation made it possible to reconstruct the chronology of Rhône floods over the last 9500 years. A comparison of this series with local palaeoenvironmental records showed the so-called “Medieval Warm Period” (MWP) which was marked by reduced terrigenous inputs in response to reduced hydrological activity. Hence, this period was marked by a lowering of the water level in the Rhône, a drop in snow precipitation in the Chartreuse massif, and an excess of water in Vercors. Keeping in mind such a limit depends largely on the archive used, our continuous record suggests the following limits for the MWP: 600-1150 AD, and for the Little Ice Age (LIA): 1150-1900 AD. On the long term, we have shown that the Holocene was a generally dry period in the Alps, whereas a trend toward more humid conditions was begun in 4200 cal. BP and was reinforced in 2700 cal. BP. Our data suggest that the LIA was one of the most humid periods during the Holocene. These interpretations are in accordance with data from the literature regarding Holocene glacier fluctuations, particularly in Switzerland and Austria.