Snowcapped Ausangate (6372m), the highest mountain in southern Peru, can be seen from Cuzco on a clear day. Hiking a circuit around its skirts is the most challenging alpine hike in the region. It takes five to six days and crosses four high passes (two over 5000m). The route begins in the rolling brown puna (grasslands of the Andean plateau) and features stun- ningly varied scenery, including fluted icy peaks, tumbling glaciers, turquoise lakes and green marshy valleys. Along the way you’ll stumble across huge herds of alpacas and tiny hamlets unchanged in centuries. The walk starts and finishes at Tinqui, where there are warm mineral springs and a basic hotel, and mules and arrieros (horsemen) are available for about S30 per day each. Average price is US$500 for an organized, tent-based trek with operators such as Mayuc Cusco  www.mayuc.com