While Cusco and Machu Picchu are obligatory destinations for a first trip to Peru, the country has much more to offer, as the pages of this guide attest. There is too much to see and do in one trip, so plan your itinerary according to your interests and the season.
Wherever you go, build some downtime into your itinerary, especially your first day in the Andes, when you may feel weak or ill. Don't let all those churches, ruins, convents, and museums blur together. Give yourself enough time to stop and smell the pisco sours.
For years travelers avoided Lima, which would be a mistake. The country's capital is a sprawling metropolis with horrible traffic and more than its share of slums, but the plazas and colonial churches of the historic Centro are impressive, Barranco is charming, and the metropolitan area has the country's best museums and restaurants.
Postpone that diet. "Amazing" is the only way to describe what we think is the hemisphere's best food. A mix of European, indigenous, Asian, and African influences makes Peruvian cuisine remarkably varied and delicious. The seafood is excellent, and the best is found in Lima and other coastal cities, but Cusco and Arequipa have ample selections of restaurants that serve up some tasty regional dishes.
Shopping is another popular distraction from exploring, and the handicraft selection is impressive, especially in Cusco. In the market and all but the fanciest shops in the Andean cities you are expected to bargain, so don't be shy.
Try to learn a few words of Spanish. Outside the tourist industry few people speak much English. Learning some common words and phrases can simplify life, and make your trip more pleasant. (Spanish is a second language for many Peruvians, too.)
Pack reserves of patience. Peru offers a polished tourism product, but schedules occasionally go awry, traffic in the cities is chaotic, and street hawkers or beggars can get on your nerves.