"And before Littlestone goes on more wild speculations.... Gorsey bigbury entrance is 13 ft wide, if it was stone gateposts we get back to the problem of hinges to hang the gates........... ;)"
We keep coming back to the stones and the Wessex henges. I started this thread by looking at the stoneless henges of Essex. If there were any gate posts there, they wood have hung on wooden posts. Gaps can be closed by other means than gates