Build as big a chunk of open space as you want! These are the "Romulan Border" panels which line up quite nicely and which are flat and smooth. They have 5/8" hexes on one side and 1.25" on the other side and are "geomorphic" which means you can plunk them down in any order and they will line up nicely in either scale. (Avoid using some panels with one scale and some with the other scale as this will confuse everybody.) These are mostly open space maps but every sixth one will be a "rosette" panel. You don't have to order in sixes.