I had some interesting design challenges here. The cage is longer than the area for the base, and I have curious dogs, so the cage had to be rock-solid sturdy. It is! I also had to maximize useable floor space, as the cage base is only 2x3. There's virtually no obstructions to it, though, and the piggies popcorn all over the place in it. The full upstairs level is L shaped, 1x3 with an attached 1x1, and contains a 1x2 kitchen and a sleeping loft (it ordinarily has a pigloo in it, removed for photo purposes).