likewise. Notices have to be tried first, don't they.
If they really did close the tomb, it could lead to really stupid people doing idiotic damage like they did at Stoney Littleton when that was sealed - people so desperate to get in/unblock it for whatever reason that they broke the stones around the doorway. Which in my mind didn't show a great deal of respect for the barrow or anybody who has ever had an interest in it.