We have a box and tunnel arrangement at the back of the lounge (here are two views of it from different angles)
We have our maze which serves as The Bunny-Mint building
Which of of course Pry-Minister Millie-Millie-Millie-Millie Bun-Bun-Bun-Bun spends a great deal of time werking in
But without any doubt, my overall favourite is the upstairs tent!