This paper describes the development of a prehistoric landscape by the river Nene at Grendon Lakes, partly revealed in the 1970s and partly during excavations in 1998 and 2001, which are reported in full. Two major phases of archaeological activity are evident, one interpreted as Neolithic–Early Bronze Age, the other as Iron Age. The gap between these is bridged by an environmental sequence reconstructed with the aid of a pollen core from an adjacent palaeochannel, which shows that human activity continued in the intervening period. The landscape is comparable in form, though not in scale, with that investigated 13 km downstream at Raunds, and helps shed light on the distinctive features of Midlands river valleys like the Nene in prehistory. In conclusion it is suggested that the different characters of the Neolithic and Iron Age features at Grendon mask some underlying similarities in the way they structured people's movements and encounters.