Fairly well preserved earthworks of large and complex multivallate Neolithic causewayed enclosure. Situated on Brighton racecourse, the site has suffered some damage via incursions by the racecourse and associated developments, as well as minor roads and housing. Excavations occurred in 1929, 1932-3 and 1935. An associated ditch was examined in 1991 during development adjacent to the site. The earthworks were surveyed by RCHME in 1993-4 at the request of English Heritage and Sussex County Council, and the site has been reassessed as part of the RCHME project on Neolithic Causewayed Enclosures and related sites. See the archive report for full details. The site comprises four circuits of interrupted ditch, the outermost enclosing an area circa 300 metres by 200 metres (roughly 6 hectares). Traces of a bank exist for all circuits. The second circuit is unusual in appearing to feature an external bank. Tangential ditches noted as early as 1821 have tended to be regarded as part of the Neolithic monument, although they appear to be quite late in the constructional sequence and may be better regarded as linear earthworks, perhaps field boundaries, of Bronze Age date. An anomalous oval mound on the north side of the second circuit may possibly represent a long barrow.