in or the Great Wall
of China. We know from tradition that war was frequently waged between
the peoples of the Titicaca Basin and those of the Urubamba and Cuzco
valleys. It is possible that this is a relic of one of those wars.

On the other hand, it may be much older than the Incas. Montesinos,
[3] one of the best early historians, tells us of Titu Yupanqui,
Pachacuti VI, sixty-second of the Peruvian Amautas, rulers who
long preceded the Incas. Against Pachacuti VI there came (about 800
A.D.) large hordes of fierce soldiers from the south and east, laying
waste fields and capturing cities and towns; evidently barbarian
migrations which appear to have continued for some time. During
these wars the ancient civilization, which had been built up with
so much care and difficulty during the preceding twenty centuries,
was seriously threatened. Pachacuti VI, more religious than warlike,
ruler of a people whose great achievements had been agricultural
rather than military, was frightened by his soothsayers and priests;
they told him of many bad omens. Instead of inducing him to follow
a policy of military preparedness, he was urged to make sacrifices
to the deities. Nevertheless he ordered his captains to fortify the
strategic points and make preparations for defense. The invaders
may have come from Argentina. It is possible that they were spurred
on by hunger and famine caused by the gradual exhaustion of forested
areas and the subsequent spread of untillable grasslands on the great
pampas. Montesinos indicates that many of the people who came up
into the highlands at that time were seeking arable lands for their
crops and were "fleeing from a race of giants"--possibly Patagonians
or Araucanians--who had expelled them from their own lands. On their
journey they had passed over plains, swamps, and jungles. It is obvious
that a great readjustment of the aborigines was in progress. The
governors of the districts through which these hordes passed were not
able to summon enough strength to resist them. Pachacuti VI assembled
the larger part of his army near the pass of La Raya and awaited the
approach of the enemy. If the accounts given in Montesinos are true,
this wall near La Raya may have been built about 1100 years ago,
by the chiefs who were told to "fortify the strategic points."

Certainly the pass of La Raya, long the gateway from the Titicaca
Basin to the important cities and towns of the Urubamba Basin, was the
key to