Five main excavations and a number of smaller ones were undertaken in advance of the construction of the A27 Westhampnett Bypass near Chichester, West Sussex, in 1992. This volume presents the evidence for settlement and related evidence that spans 11,000 years from the Late Upper Palaeolithic to the medieval. The sites examined included a Late Upper Palaeolithic palaeosol, two early Mesolithic residential base camps, isolated Early and Late Neolithic pits, an Early Bronze Age barrow and a Middle Bronze Age settlement, a Middle Iron Age settlement, an unusual Romano-British enclosure of unknown function, perhaps a shrine, and an Anglo-Saxon Sunken-Featured building. These excavations provide the first archaeological transect across part of the West Sussex Coastal Plain and provide a useful contrast to the well-explored Sussex Downs immediately to the north. The Iron Age, Romano-British and Anglo-Saxon cemeteries are published in volume 2.