6/24, Saturday, Inti Raymi, the sun festival. This site offers detailed descriptions and nice photos.
All started at ~9:20am at the grassy square of Qoricancha. It took half an hour for all groups of performers to appear, men first, then the chosen women. A high priest gave a speech (all in Quechua) from the balcony of Qoricancha casting some plants down to the spectators. Finally the Inca came out, calling for God. At ~10am, the royal followers walked along Pampa del Castillo and Loreto, to Plaza de Armas, carrying Inca and his queen in elevated seats. From there, the whole assembly marched up to Sacsayhuamán.
We lunched before joining the hordes at Sacsayhuamán. Needed some food in order to hike up the rather steep 2km slope. By the time we arrived (~2pm), it was difficult to find a spot on the surrounding hills. (For $80, you can buy a seat from a central office ahead of time. Maybe the most profitable show on earth!) Many people picnicked here. Women selling popcorns and popsicles. Looked like a family outing day. Some of them didn't seem to care about the spectacle, settling comfortably in places completely barred from the view of the stage.
Pyres of branches and dry grass were lit, generating lots of smoke. A llama was selected and sacrificed. It started hailing before llama was killed for a short while, but didn't stall the performance. The high priest took out the entrails trying to read some future out of it. He threw a piece into the fire, and then offered the bleeding heart to the Inca, and the Inca ate a piece of it, while giving a long discourse. With the announcement of the beginning of a new year, more dances followed, until about 3pm. To me, it was equally fun to watch all the coming and going of spectators (sometimes in perilous locations), the noise, the comments, and business transactions (tossing popcorns and coins).
Finally everyone left, leaving the entire ground covered with litter. Before heading down to town, we walked over to the silly Cristo Blanco, a Brazilian present.