The path closely follows the route of the Stockade wall around central Cahokia. The wall was built four times, with each new wall replacing an older decaying one. Its primary purpose was defense, as shown by the regularly spaced bastions, and excavations here found all four bastion types superimposed upon one another. The Stockade was also built through former residential areas, revealing many earlier houses and pits. Mound 36 to the west was a rectangular platform mound, and although there have been no excavations, remote sensing tests suggest that it held a series of large circular buildings.