Chipping Hill is the site of a bivallate earthwork, traces of which remain (apparently, since I could not clearly identify them myself) beneath the modern buildings which now occupy the area.
Reputably the location of a Saxon burh built by Edward The Elder, pottery associated with the outer defences has yielded a Mid Iron Age date... so it would seem we are looking at a case of progressive site adaptation here.
It was the coming of the railway which, while cutting through the rampart during construction of the viaduct in 1850, ironically shed conclusive light upon a prehistoric presence upon the hilltop: the discovery of three burials with Iron Age La Tene II-III pokers. That’ll do.
Pastscape has details at:
heritagegateway.org.uk/Gateway/Results_Single.aspx?uid=MEX26167&resourceID=1001