Pisac is one of Cusco’s few great Inca ruins that features all types of architecture—agricultural, hydraulic, military, residential, and religious. It probably began as a military garrison to guard against incursion from the Anti Indians, who occupied the easternmost corner of the empire known as Antisuyo (present-day Paucartambo and the Manu jungle).  There are several ways to see the Pisac Ruins (7 a.m.–3 p.m., admission with Cusco ruins ticket), but the best is to take a US$3–4 taxi up the 8-km highway to the ruins. Instead of going to the main entrance, tell your taxi to head right on the switchback and head farther up to the Pisac ruins of Qanchisracay. From here a trail leads along a ridge, through a tunnel, and down into the Intihuatana, or the main sun temple. The walk is steep and exposed to heights, but safe. Or arrive at the Intihuatana via the main path from the main entrance. Allow for one or two hours for walking around the ruins (return to town via taxi) and another two hours for walking downhill all the way to town.