I may have got hold of the wrong end of the stick here but what sprang to mind for me were the following examples:

Holy (sacred) Islands - such as Iona, Lindisfarne, St Michaels Mount etc - where there is evidence of pre-christian use as a sacred site.

Hills - such as Glastonbury and various natural hills around Wiltshire.

Wells and springs - that have had healing qualities attributed to them, again with evidence of pre-christian activity.