Earthen Platform Mounds

artist depiction of Compound B in ancient times
Robert Ciaccio artwork, part of the wayside image

Commissioned art with restricted use

Look at the mounds of dirt 100 yards ahead. They are man-made. Picture them 900 years ago, covered with buildings and plazas and people, all inside a rectangular 7-foot-tall wall.

Imagine the work it would take to make such a 10-foot-tall base platform by hand, then build a complex like you see in this illustration atop it. Archeologists have found about 50 platform mounds like these here in southern Arizona.

The mounds you see are about five feet taller today than they would have been centuries ago. National Park Service archeologists have covered these platforms with backfill to preserve and protect them.

Backfilling involves reburying ruins with soil. This preservation method cannot stop deterioration, but it can slow down erosion and stabilize the site.

Agricultural Connection?
Archeologists find most platform mounds at the beginning or end of large canal systems.


A PDF of the wayside (6,673 KB) is available.


Last updated: April 6, 2020

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