The Baiju Monastery (Xinhua/Purbu Tashi)

For every year, on the 15th day in the first month of the Tibetan calendar, Tibetan people mark the end of the new year festival with a "fight" of zanba.

A man beams with zanba flour on his face. (Xinhua/Purbu Tashi)

Zanba is the staple food in Tibet. The roasted highland barley flour is mixed with yak butter and usually squeezed into a dough before eating.

The Baiju Monastery (Xinhua/Purbu Tashi)

The best place to witness the ceremony is the Baiju Monastery, which perches on a highland 3,900 meters above sea level. It's about 230 kilometers south of Lhasa.

Tibetans gather in the Baiju Monastery on March 12, 2017. (Xinhua/Purbu Tashi)

On this special day, people would wake up early and get to the monastery before sunrise, carrying zanba flour with bags on their back.

Tibetans put prayer flags on a pillar at the Baiju Monastery on March 12, 2017. (Xinhua/Jigme Dorje)

But their first job is to change the prayer flags on the four pillars in the temple with new ones. The pillars, over 30 meters high, would be totally covered by new flags when most people arrive.

People erect the pillar with prayer flags on it on March 12, 2017. (Xinhua/Purbu Tashi)

People pull the ropes to erect the pillar with prayer flags on it on March 12, 2017. (Xinhua/Purbu Tashi)

The carnival begins when the first pillar is erected.

People pull the ropes to erect the pillar with prayer flags on it on March 12, 2017. (Xinhua/Jigme Dorje)

Zanba flour is thrown all over the place, and at everyone. Bless of pure white is thus spread, to families, friends and even strangers.

A man in the "white fight". (Xinhua/Jigme Dorje)

Caught white-handed (Xinhua/Jigme Dorje)

Men in big smiles after the "fight". (Xinhua/Jigme Dorje)

Everything at the temple is obscured in white when all the people are involved in the "fight".

People pull the ropes to erect the pillar with prayer flags on it on March 12, 2017. (Xinhua/Jigme Dorje)

The ceremony has been held for over 600 years. No one knows how exactly it began, but now people believe it is a praying ceremony for favorable weather and bumper harvest.

People wait for a "battle" before a pillar of prayer flags is erected. (Xinhua/Purbu Tashi)

The flour won' t be wasted. It would be collected and fed to livestock.

An old man in the zanba fight (Xinhua/Jigme Dorje)