So I've got a series of paper maps for a dungeon. I'm looking for a good way to hide the rooms from the players until they walk in that is easy to undo and won't tear the maps.
I use 5x7 notecards. Just spread them over the whole map ( overlapping, not neatly tiled) and then slide them out of the way as the PCs explore. 1 or at most 2 packs will cover a whole map. I keep them in a quart size ziplock and reuse them.