Cusco was the centre of Tahuantinsuyo, the empire that at its height stretched from southern Colombia to central Chile. The Spanish did not raze the city — they built on top of it. That is why the historic centre is a palimpsest, with baroque churches resting on Inca ashlar foundations that have outlasted several earthquakes while the colonial structures above came down.
Start at the Qorikancha
The Qorikancha, the Temple of the Sun, explains the whole city. Its walls were sheathed in gold plate and its chambers housed the empire's principal deities. The convent of Santo Domingo was raised directly on top. Today you see both at once, and the contrast between Inca stonework — blocks fitted without mortar, to a precision still hard to account for — and colonial masonry is the best history lesson Cusco offers.
Above the city, a twenty-minute climb away, stands Sacsayhuamán, a ceremonial fortress with blocks of over a hundred tonnes fitted to the millimetre. You can walk up from the San Cristóbal square, though at this altitude it is worth taking slowly. The same road continues to Q'enqo, Puka Pukara and Tambomachay, three smaller sites easily seen in one morning.
San Blas and the stone lanes
The San Blas quarter, uphill from the Plaza de Armas, is full of artisans' workshops, houses with wooden balconies and a church whose carved pulpit is among the finest pieces of religious woodwork on the continent. On the way, in Hatun Rumiyoc street, sits the famous twelve-angled stone, set into a wall that was once the palace of Inca Roca.
Altitude is a serious matter
The city lies at 3,400 metres. Soroche — altitude sickness — affects a great many visitors and has nothing to do with fitness. For the first twenty-four hours, avoid carrying luggage uphill, eat lightly, drink water and skip alcohol. Coca tea helps a little; if symptoms worsen, any pharmacy sells acetazolamide, though it is worth discussing with a doctor before you travel.
Eating without falling into the trap
The Plaza de Armas is ringed by restaurants with laminated menus and touts at the door. Two streets further out you eat better for far less. The San Pedro Market, designed by Eiffel's workshop, serves chicken broths, Amazonian fruit juices and set lunches at long shared tables. In the upper neighbourhoods you will find picanterías, where chiriuchu, Sunday-morning Cusco-style adobo and oven-roasted cuy are made exactly as they always have been.