Defensive Outposts along the Wall
To capture the activities that once took place in the observatory outposts attached to the elongated defensive wall, we excavated one of them. The gateway room that strategically controlled access to the lower complex was selected for closer examination (Structure-16) (Figure 7.1). Judging by the wall seams, this outpost was likely a late addition to the earlier defensive wall. Perhaps it was built to strengthen its defensive character. In fact, the excavations revealed a long occupation. Over the sterile soil we found the remains of an early stone platform that perhaps extended along the entire wall. Similar defensive platforms have also been documented for other Inka military installations, such as Inkapirca-El Rosal in Khosko Toro and Pucara de Andalgala in today’s northern Argentina (Hyslop 1980:185).
Inside the outpost, we also recovered the remains of a hearth (Feature 11) that could have been used for temporary cooking or to keep the wall guards warm during the night shifts. Within the hearth pit we recovered a concentration of ash and charcoal, and because the remains were not stratified, this feature might have been used for a short but intensive time. There were also utilitarian fragments, camelid bones, ash lenses, and charcoal flecks spread on the living floor. Therefore, it is likely that this outpost served simultaneously as a temporary residence and shelter for the soldiers posted in the defensive wall. Calibrated AMS analysis dated the hearth around A.D. 1327-1342 and A.D. 1394-1423, at one sigma error (68 percent confidence). This date range indicates that the outpost was one of the earliest features of the entire complex (Figure 5.6; Table 5.1; sample AA36940).
In the second episode, there was evidence of a generalized fire event that prompted the abandonment of the outpost. This is signaled by the deposition of a thin layer of brown clay mixed with large quantities of charcoal flecks. I suggest that this relates to the invasion of the Cuzcotuyo fortification by the invading Chiriguano hordes reported in the ethnohis- torical narratives (Parssinen and Siiriainen 1998).
Despite this obliteration, the entire fortification was reconstructed and reoccupied. Architecturally, some sectors in the main building were amplified and the main gates blocked. More important, a thick matrix of yellow clay mixed with gravel used as a refurbishing floor covered earlier burning destruction events. This renovated floor was documented in the main building complex and in the private rituals room (Structure-15). However, not many cultural remains were associated with this new surface. Sometime later, the entire stronghold was abandoned.