CUSCO, located in the Southern Sierras, is a fascinating city that was the capital of the Incan Empire. As a Unesco World Heritage Site, it is one of Peru's most visited cities as it is the largest and most comfortable place from which tourists can begin visits to Machu Picchu, the Sacred Valley of the Incas, and other Incan sites in the region. It is beautiful, with well preserved colonial architecture, evidence of a rich and complex history. The city itself represents the center of indigenous Quechua culture in the Andes, and by merely walking the streets one sees the layers of history. It is surrounded by a number of ruins, the most impressive being Sacsayhuaman, the site of the 1536 battle in which dozens of Pizarro's men charged uphill to battle the forces of the Inca.