Another thing I do, is I have a clip board I ripped the clip off of, if you use pliers on the rivets you can do this without ruining the board itself. Then I clip my map to the board with binder clips. That way the map is fixed to the board on all sides and doesn't flap in the wind or get damaged.
_________________________
A gentleman should always be able to break his fast in the manner of a gentleman where so ever he may find himself.--Good Omens