Excavations made necessary by coastal erosion have revealed probably the best preserved Bronze Age settlement sequence in Southern Britain. Five metres of deposits contained five prehistoric occupation phases separated by blown sand and eroded soil. The two lowest horizons, containing Beaker pottery, were followed by a layer with biconical urns and an oval stone structure; then came a rich middle Bronze Age layer with two round houses superseded by a late Bronze Age midden type deposit which produced two gold bracelets. At the top was a sub-Roman cemetery. The Bronze Age layers contained an abundance of pottery and other artefacts, including fired clay objects which represent one of the earliest salt extraction sites in Atlantic Europe. Environmental evidence was also prolific and contributions are included on soil thin sections, chemistry, magnetic properties, pollen, diatoms, ostracods, charred plant remains, animal bones, coprolites, and molluscs. The site seems to have been an island in the Bronze Age, with a considerable expanse of infrequently inundated saltmarsh to its south. The causes of the alternating sequence of sand deposition and stabilisation are considered in the context of environmental change generally in the Severn Estuary and the Somerset Levels.