"We went to the Oregon Garden a few days ago, and I was happy to see this “hobbit hole” in the children’s garden! I would love to have one of these in my yard!! It was made with a big drainage tube, and had round plywood doors on each end of the tube. The earth had been mounded over the tube and then covered with grass and plants. They built a nice T-shaped door frame over the hobbit door, and there you go! "