Abstract Insect faunas from organic deposits laid down by the Warwickshire Avon dating from the late Bronze Age were examined and their environmental significance assessed. It was concluded that the local countryside was open grassland with evidence of large grazing mammals. The river Avon at this time seems to have had a clean, stony bed without the blanket of mud and silt which forms the bottom today. A climate slightly warmer than that of the present time is suggested. Comparison is made with faunas of sites of the same or similar ages.