"No Weapons Except As Permitterd By Law" means generally that they do not have a leg to stand on but are hoping that the vast majority will erroneously believe they must have some sort of special permission slip in order to carry there.
Because Buckroe Beach is part of a local government municipality, state preemption is in force. Unless something special is happening there (e.g.: area is being used exclusively for a school function) they cannot close off an otherwise permissable area. BTW - if it was being used exclusively for a school function, how would you get to be there in the first place?:uhoh: (We will not discuss the AG's wrong and idiotic ruling concerning municipal property rented by a third property.:cuss::banghead::cuss
IIRC Fortress Monroe is now a state park. Carry at state parks is permitted.
stay safe.