Cumbe Mayo
This pre-Inca site, 16 km (10 miles) southwest of Cajamarca, is surrounded by a large rock outcropping where you'll find petroglyphs left by the ancient Cajamarcans. There are also petroglyph-adorned caves, as well as a 3,000-year-old network of Andean aqueducts. The site, discovered in 1937 by the famous Peruvian archaeologist J.C. Tello, may have been designed to direct the ample water from the mountains into the drier area of Cajamarca, where there was a large reservoir. Amazingly, more than 8 km (5 miles) of the ancient aqueduct are intact today. Guided tours (required) cost around S/35 and take about four hours.