Cusco was originally designed to take the shape of a puma, which, along with the condor and the snake is a sacred animal for the Incas. Today I'm walking down its backbone, the Avenue del Sol, to pick up some extra supplies for the trail which starts on Wednesday. I manage to pick up a flashlight and some hybrid glove-mitten things, complete with the obligatory llama design.

The key Incan ruin around Cusco is Sacsayhuaman (pronounced something like "sexy woman"). It is located at the head of the puma street design, and is said to hold the knowledge of the city. A temple to the sun and thunder gods it takes the form of giant stones (the largest estimated to be 300 tonnes) perfectly fitted together like a jigsaw, which terrace the mountain-side. The nearby sites of Tambo Machay and Qenko are where the shrine to the god of water and a site for human sacrifice are located.

In the town centre, the Cathedral contains another version of the Peruvian Last Supper - this one is more explicit with the guinea pig plonked in the middle of the table as though it had just been electrocuted. There are other Catholic-Andean compromises such as the arm rests of the seats which feature Andean fertility symbols (a pregnant woman with a phallus for legs).

The Temple of the Sun is the most explicit example of the Spanish buildover project, with some of the original Incan temple still in tact, but with doorways half blocked by the church.