I am using two wooden horses and two really tough planks of oak to support the set. Their were a bunch of old doors in the rafters so I brought those down and layed them side by side.  Then I used large plastic sheets to cover them. This will seal them from all the moisture that the dirt will bring after I use water to harden the dirt. Since there will be so much weight on top of the doors I am going to use some more support in the middle. The small front section i wanted to make a little peak between the trees. it turned out kinda cool so i set up some lights on it to see what I had.