Legends of Biru Skull Wall

According to Duoduoka's celestial burial master, there were originally three monasteries where skulls were kept after celestial burials: the Duoduoka Monastery, the Ridazeng Monastery opposite the former and the Quedai Monastery nearby. Biru has gained its fame from containing all three monasteries. Unfortunately, most of the skulls have been damaged both by natural and manmade disasters. By the early 1980s, most of skulls in the Ridazeng and Quedai monasteries have disappeared, despite a very supportive governmental policy in preserving religious relics.

But why skulls are kept in the celestial burial of these three monasteries remains a mystery. There are currently many versions of this unique custom's origin, but two possible answers are prevailing and more accepted.
One version says that the custom was formed some 80 years ago, when an eight-year-old boy from a Tibetan tribe witnessed the killings of three people. The little boy was so scared that he ran directly to the living Buddha in Biru County, who later appointed him as a celestial burial master. He began to pile up all the skulls of the dead in the corners of the charnel ground. At his death, 42 years later he left behind a wall of skulls. It is said that he built the skull wall to prevent the killer he saw when he was eight from coming to the charnel ground.

The other version retains that the custom is a rule established by a living Buddha, whose motives remain unknown. According to Awangdanzeng, a celestial burial master, the main purpose of keeping the skulls and piling them up against a wall is to remind the living to do more good deeds and restrain from secular desires, because everybody, regardless of their living status, is the same after death.