From what I’ve seen, it’s actually pretty hard not to find Roman settlements in southern England.
Years ago, when there was still a cottage industry producing charcoal the old-fashioned way (by hand, generally a father-to-son kind of thing), one guy finally got curious about the stone floor of his pit, started digging around a bit, and discovered he’d been using the surface of a Roman road that had been covered by soil to a depth of a foot, foot and a half.