Many years after (1533), this valley was the refuge and last home of the Incas of Vilcabamba, that were able to hold out for a few decades against the "conquerors" domination after the conquest of Cusco.
The llactas are the best proof of the imperial character of the Incas, and of their intention to permanently dominate those nations they conquered. These llactas were major settlements built on the Capac Ņan road (Royal Road of the Incas) with the purpose of controlling and administering the economy of the different regions they conquered.
They were built according to a detailed plan that obeyed the need to control and retain their conquered territories. Essentially, the llactas were bureaucratic establishments where Inca administrators and all their retinue of government officers resided, together with their servants and craftsmen.
Picchu (the original name of Machu Picchu) was
one of these llactas, but played a special part. It is the only
one at a long distance from Capac Ņan, and it was built in a hidden
and unassailable part of the valley of Tampu, on lands belonging
to the panaca of Pachacutec, the founder of Tahuantinsuyo.
the most beautiful one in the empire, because it was built to be
the home and haven of the cream of the aristocracy. The roads leading
to Picchu were banned to the ordinary inhabitants, because its location
was a military secret. Its steep cliffs and wild mountains were
a perfect natural defense.
Judging from the remains found in this Inca city, in its heyday the population numbered several thousand inhabitants.
Just as did every other important llacta, Picchu possessed an acllawasi -house of the chosen maidens-, an intiwatana - sundial, also showing the seasons of the year-, kallancas -barracks for the warriors-, bath houses and aqueducts, as well as large terraced areas for crop growing.
Eighty percent (109 skeletons) of the 135 mummified corpses found in an archaeological excavation carried out by the Bingham expedition were female, a fact indicating the existence of the aqllawasi -house of the chosen maidens, the Inca's "harem"-, who were considered to be "brides of the Sun". They escaped from Cusco before the Spaniards arrived. The other theory is that Machu Picchu was almost exclusively inhabited by women.
Many modern scholars suggest that, as the heir to the throne had to be the son of the Inca and one of his sisters, a large number of these women were also the wives of the Inca. He was a living god, in view of the fact that he was considered to be the "son of the Sun". Thus, the Inca lived on his land, in the company of his wives. It was considered normal for an Inca to have hundreds of concubines.
Historical records show, for example, that Wayna Capac, father of Huascar and Atahualpa, had more than 400 children. Nevertheless, his main wife must have been his own sister, because only thus could the "blood line of the Sun" be preserved.
Even today, the reasons leading to the disappearance of Machu Picchu's population are unknown, although some logical hypotheses have been put forward.
One of these is that a sudden epidemic led to the abandoning of the fortress. This theory is supported by the fact that it was built in a humid area infested by insects. Even during the first few decades of the twentieth century there were frequent epidemics in this area, especially of malaria.
It is also argued that it was ordered closed and had to be abandoned after the death of the ruler that built and lived in the city, although this is contradicted and invalidated by the evidence that it was inhabited by at least three generations of Incas.
Another theory argues that on one occasion the Antis -groups of Amazonian Indians-, the Inca's worst enemies, reached this spot and decimated the population. The only sure fact is that Machu Picchu was closed, abandoned and forgotten until the first few years of the twentieth century.
Very possibly, however, after the Spanish conquest, and coupled with the collapse of the greatest of the empires in pre-Columbian America, the city lost its "raison d'etre". Once Atahualpa, the last Inca emperor, had been murdered at Pizarro's hands, there was no longer a need for a safe haven for the "chosen maidens".
Moreover, the amazing works of architecture and hydraulic engineering were of no interest to the rough "conquerors", and the high mountain and jungle roads would only have been useful for them had they led to sources of gold and precious minerals. Thus, Machu Picchu was lost to human memory for three long centuries.