see http://www.pastscape.org.uk/hob.aspx?hob_id=408670The brighter grass flat field,with the steep slope beside,was an iron age fort,re-used by the Normans. see http://www.castlefacts.info/contentpages/castledetails/castledetails.asp?country=England&countyid=40&county=Sussex&castleid=3771&latitude=50.8157005310059&longitude=0.172099992632866&uin=11082