126 H. E. Gregory — Geologic Reconnaissance of the 



the Apurimac River and finally emerges at the hacienda of 

 Ayusbamba, ten leagues south of Cuzco (fig. 1). For genera- 

 tions this trail has been the main avenne of approach to the 

 sacred city from the upper Apurimac valley, and the artificial 

 pavements, terraced descents, and trenched hillsides give evi- 

 dence of an originally well-planned highway, whose construc- 

 tion involved a prodigious amount of physical labor, the value 

 of which is greatly reduced by the present neglect of mainten- 

 ance. In traversing this route from Cuzco to Ayusbamba, one 

 is impressed by the thought that the llamas and picturesque 

 Indians met On the trail, the grass-covered slopes, the cacti 

 and tenaceous shrubs along the path and bordering, the artificial 



Fig. l. 





t\ ) 





U). / 





^ J 





5m / 



V 



0! \ 



fe 



7/* / 



Q) 



p//o _/ 





/i / 







/Ccoyp 







^^^usbarnba/^^^ 





\ Fossil/Locality 



Naynpal 



-£i/r^° 







Fig. 1. Index map, showing location of Ayusbamba. 



walls, the wonderfully beautiful native flowers which carpet 

 the bowl-like upper valleys, and the long vistas of canyon and 

 slope present a picture essential]}' identical with that viewed 

 by Inca and pre-Inca travelers. For eight or ten centuries 

 this well-worn path has marked the passage of llama trains and 

 patient Quichua cargadores bearing materials of trade to and 

 from Cuzco. 



Along the route are several squalid villages — groups of 

 thatched adobe or stone huts — the homes of the Andean shep- 

 herds. Midway between Cuzco and Ayusbamba the trail 

 makes a descent of 2000 feet and passes through Yaurisque at 

 a point where a canyoned stream is joined by two short, wide 

 valleys. The limestone soil, abundant water and sheltered 



