I believe, from "The Wilmington Giant", that the flint mines are roughly contemporary with the Long Mound. They are not at the most sensible height for the best hunting flints, so MAY have been significant for another reason.
Indeed. I remember from Grimes Graves that flint on the surface was damaged by the permafrost from the last ice age, hence why they dug down so far. Has anyone ever excavated the mines?
Oh and do you know how far the cursus goes at the bottom of the hill?