If you visit Monks Mound in the early morning, before the visitors arrive and the interpretive center opens, the mound is simply there.

It rises out of the flat Illinois landscape in a way that seems improbable, not because it is obviously artificial — though it is — but because its scale is difficult to reconcile with the surrounding environment.

It is too large.

It belongs to a different category of thing than the fields and roads and buildings that surround it.

Standing at the base of the mound and looking up at its southern face, you can see, if you know what to look for, the faint lines in the earth that mark the edges of different construction stages — the places where new soil was added to raise the platform higher, creating a stratified record of the building process that stretched over several centuries.

The mound is, in this sense, a kind of document — a physical record of the decisions made by hundreds of generations of workers and leaders, of the sustained commitment to a project that would not be completed in any individual’s lifetime.