Palaeoenvironmental and archaeological investigations have been in progress since 2 years, 70 km upstream from Lyon, in the upper Rhône valley. A multi-disciplinary team (palaeogeography, palaeoecology, archaeology) is attempting to reconstruct the spatio-temporal fluctuations of the nver and their origin through the survey of meandering palaeochannels A first spatial approach allowed us to identify several meanders Phases of channel change are identified from the recent Atlantic penod until the Subatlantic penod (Modern Times). Detailed stratigraphical study of 6 palaeomeander fills is undertaken Cores have been taken from pool fills units, up to the sandy-gravel bottom (6 meters m depth on the average), for palaeoenvironmental analysis. A chronological framework has been established (14C dating, palynology). The first results provide new information on fluvial dynamics and allow us to propose a reconstruction of the Basses Terres floodplain evolution during the Holocene Some archaeological investigations have been earned out m the alluvial plain. The goal is to assess the human activities pressure on the sector and their impact on the environment.