The cliffs are often sloping, sometimes overhanging, but more
frequently perpendicular. The weather erosion of many centuries
has caused the softer strata of exposed rocks in the cliffs to
disintegrate and fall away, which left numberless caverns wherein
this ancient and mysterious people chose to build their eyrie
homes to live with the eagles. The houses are built of all
shapes and sizes and, apparently, were planned to fit the
irregular and limited space of their environment. Circular watch
towers look down from commanding heights which, from their shape
and position, were evidently intended to serve the double purpose
of observation and defense.

In the search for evidence of their antiquity it is believed that
data has been found which denotes great age. In the construction
of some of their houses, notably those in the Mancos Canon, is
displayed a technical knowledge of architecture and a
mathematical accuracy which savages do not possess; and the fine
masonry of dressed stone and superior cement seem to prove that
Indians were not the builders. On the contrary, to quote a
recent writer, "The evidence goes to show that the work was done
by skilled workmen who were white masons and who built for white
people in a prehistoric age." In this connection it is singular,
if not significant, that the natives when first discovered
believed in a bearded white man whom they deified as the Fair God
of whose existence they had obtained knowledge from some source
and in whose honor they kept their sacred altar fires burning
unquenched.

The relics that have been found in the ruins are principally