" A section excavated in 1950 by F.G. Simpson through the earth
bank showed it to be of turf sod construction, and upon this evidence
the fort has been dated to the Dark Ages, perhaps the 5th or 6th
century."
I can't help but think that that doesn't mean that the actual Tor didn't have some prehistoric significance. I've never been to carl Wark, but looking at the pics and reading the notes, I'm reminded of some weird multi-era sites I've seen in Northumberland.