Inti Raymi was the biggest, most important festivity ever carried out in Inca (Inka) times.
Today is still celebrated annually in Cuzco and the archaeological complex of Sacsayhuaman, attracting hundreds of thousands of visitors from all over the world.
It's the second biggest celebration in South America after Rio's carnival.
Inti Raymi comes from Quechua language, which means "resurrection of the sun".
Inca religion centered on the worship of the sun.
The Inca emperor - Sapa Inca - was worshiped as a god who was descendant of the Sun god - Apu Inti.
The living representative of Inti on Earth.
According to Inca mythology, Inti was the Sun god, son of Viracocha, creator of civilization.
Original people were flood survivors who were saved and repopulated the Earth. Viracocha came to the Andes to restore civilization, culture and knowledge after the flood.
Inti Raymi marks the beginning of a new year.
It was carried out at the end of the potato and maize (corn) harvest in order to thank the sun for the abundant crop, or otherwise to ask for a successful one during next season.
The date was June 24th.
Scientifically, the winter solstice in the Southern Hemisphere begins on June 21st., but according to the Pacha Unachaq - sundial used by the Incas - the sun remains some days at the same place before rising on the 24th.
Inti Raymi festival began with a fast of three days.
No fire was lit and people had to refrain from having sex.
The celebration would last for nine days.
All preparations were carried out in Koricancha - Sun temple - the Aqllawasi and Wakaypata - Cuzco's main square.
The Inca emperor - Sapa Inca - would offer Aqha - chicha (an alcoholic beverage made of fermented corn) - to the sun.
He would drank a sip of it and the remaining was drank by the nobility and later by every attendant.
The High Priest had to perform the llama sacrifice, offering a complete black or white llama to Inti, using a ceremonial knife called "Tumi".
After opening the animal's chest, he pulled out its heart and viscera, and had to foretell the future by observing those parts.
After the sacrifice, he had to produce the Sacred Fire.
Inti Raymi continued by priests offering Sanqhu - some kind of holly bread - made of corn flower and blood of the sacrificed animal.
After all stages of the celebration were completed, all attendants were nourished and entertained with music, dances and Chicha.
Inti Raymi Celebration
Inti Raymi was banned by Viceroy Toledo in 1572.
It was considered as pagan and contrary to the Catholic faith.
For over fifty years now, Inti Raymi is celebrated ath the archaeological complex of Sacsayhuaman, with some 500 actors recreating all stages of the ceremony - the llama sacrifice is obviously not carried out effectively.
It's a very special day for Cuzco's inhabitants and visitors alike, before, during and after June 24th.
There are street celebrations, exhibitions, live music and dances staged at Cuzco's plaza de armas.