The ruins in Square Tower Canyon are classified for convenience in
description as follows:
(1) Ruins which have indications of inclosed circular kivas, with
mural pilasters and banquettes, and closely approximated surrounding
rooms. To this class belong ruins 1, 2, and 10. Of these, Unit type
Ruin (No. 10) has only one kiva and belongs to the simplest or unit
form of the pure type. Ruins 1 and 2 have two or more kivas and are
formed by a union of several units, combined with towers and great
houses. (2) Ruins, the main feature of which is absence of a circular
kiva. The Twin Towers belong to this second or “great house” type. The
few cliff-dwellings in this canyon are small, generally without kivas,
resembling storage cists rather than domiciles.