While in Peru, make sure to take a 3-day tour to see Cusco and one of the new 7 wonders, Macchu Picchu.
A lot of company offer the same 3-day tour where you will have a chance to see beautiful Inca sites, proof of the greatness of the empire.
Cusco City, the historical capital of the Inca Empire and its Cathedral La Iglesia and Convento Santo Domingo on the main square Plaza de Armas and the Inca landmark of Qorikancha. At night, the Plaza is very lively and all the restaurants and bars are full of locals and tourists.
Right outside of the city, you will be able to see other Inca landmarks like the archeological site of Tambomachay, the citadel of Sacsaywaman, the Huayllay National Sanctuary and the village of Ollantaytambo in the sacred valley. You will stop at Mirador Taray, the place to have the best view of Cusco and the surrounding nature.
Macchu Picchu is a day trip by itself. You will take the blue train to the Macchu Picchu city called Aguas Calientes . From there, you will take a bus to the ruins. Be ready to start some walking but it is so worth it. You will soon be able to witness the breathtaking 15th Century Inca site. The scenic is just breathtaking.
Back in Lima, make sure to head to Downtown, The place for shopping but also to admire the old streets and some fine architecture works.