User blog comment:Googleaarex/Hierarchy of space/@comment-39162-20141003064824

Well, three is better than two!

For more fun reading on this topic, have a look at Ekistics (a hierarchy for human settlements such as cities) and Biological Organisation (a hierarchy for biological organisms).

You'll notice that I combined the two in my hierarchy, linking the single human of the settlement hierarchy to the organism of the biological hierarchy.