hi!, South America is a wonderful place, really interesting to visit and explorer, I can recommended about Peru we have many beautiful places as Arequipa where we can found the Colca canyon and the Misti vulcano, Cusco where is located Machu Picch citadel and many others ruins to visit as Sacsayhuaman, Quenqo, Choquequirao, and the impressive inca trail, other place very interesting is Puno where we can see the beautiful titicaca lake, and the Uros´s island, a comunity of natives who lives in a island in the titicaca lake, other place is the jungle of Peru, places like Iquitos, Tambopata reserve, Manu reserve, natural, ecologic and magical places, there are a lot of plants, animals and natives tribes, Huaraz is another option to people who likes snow, climb and mountains, and for sure the Nazca lines and the Paracas reserve in Ica. We have in Peru many paradises and beautuful places to take a long vacations, so if just have a short time, you can choose some of them or mange your time.
Thats all i can tell, good luck and have a nice trip.
Good bye
Cecilia