between Dover and St Margaret's bay, not that ancient, but the subject of much of the technical development of lighthouse operation and navigation ( http://www.engineering-timelines.com/scripts/engineeringItem.asp?id=740
There were lighthouses here from Roman times to help keep shipping of the Goodwin Sands which have claimed 2000 recorded wrecks and possibly as many not recorded https://en.wikipedia.org/wiki/Goodwin_Sands