colca, which are
usually thought of as a fortress.

Squier says that this "fortress" was "the southern limit of the
dominions of the first Inca." "The fortress reaches from the mountain,
on one side, to a high, rocky eminence on the other. It is popularly
called 'El Aqueducto,' perhaps from some fancied resemblance to an
aqueduct--but the name is evidently misapplied." Yet he admits that the
cross-section of the wall, diminishing as it does "by graduations or
steps on both sides," "might appear to conflict with the hypothesis
of its being a work of defense or fortification" if it occupied
"a different position." He noticed that "the top of the wall is
throughout of the same level; becomes less in height as it approaches
the hills on either hand and diminishes proportionately in thickness"
as an aqueduct should do. Yet, so possessed was he by the "fortress"
idea that he rejected not only local tradition as expressed in the
native name, but even turned his back on the evidence of his own
eyes. It seems to me that there is little doubt that instead of the
ruins of Rumiccolca representing a fortification, we have here the
remains of an ancient azequia, or aqueduct, built by some powerful
chieftain to supply the people of Piquillacta with water.

A study of the topography of the region shows that the river which
rises southwest of the village of Lucre and furnishes water power
for its modern textile mills could have been used to supply such
an azequia. The water, collected at an elevation of 10,700 feet,
could easily have been brought six miles along the southern slopes
of the Lucre Basin, around Mt. Rumiccolca and across the old road,
on this aqueduct, at an elevation of about 10,600 feet. This would
have permitted it to flow through some of the streets of Piquillacta
and give the ancient city an adequate supply of water. The slopes
of Rumiccolca are marked by many ancient terraces. Their upper limit
corresponds roughly with the contour along which such an azequia would
have had to pass. There is, in fact, a distinct line on the hillside
which looks as though an azequia had once passed that way. In the
valley back of Lucre are also faint indications of old azequias. There
has been, however, a considerable amount of erosion on the hills,
and if, as seems likely, the water-works have been out of order for
several centuries, it is not surprising that all traces of them have
disappeared in places. I regret very much that circ