The Springfield Cemetary gates, the three tombstones, the two trees, and the Krusty doll are all removable. Pegs protrude from the bottom to fasten them to the base.
The base has the traditional three buttons and plugs for figures.
Since the backdrop is folded cardboard, it might be difficult to find one alone down the road should yours get damaged. An enlarged scan (1.7 megs) of it is available here. It is significantly larger than actual size and hi-res, in case one may decide to use it as a background or edit it to print out as a replacement should one be needed. The original background was marked with the points on which to fold, as shown in the scans.
The decision to hide Kang and Kodos with the cemetary gates baffles us.