An old Darhad man is reading ode for the Genghis Khan. [Photo by Wang Kaihao/China Daily]

Though no one knows where the Khan was actually secretly buried. This mausoleum commemorating the Khan guards some of his belongings and images, as well as spear-shaped totems called sulde, which are sacred to all Mongolians.

The Darhad has scrupulously kept an oil lamp in the palace burning uninterruptedly for nearly 800 years as part of their sacred duties.

About 6,000 Darhad people now live in Ejin Horo, which translates to "courtyard of the Emperor Lord". More than 30 still perform full-time duties guarding the place and hosting dozens of rituals every year, among which Tsagaansurek is the biggest.

The complicated process of rituals has stayed unchanged through centuries and is among the first list of national intangible cultural heritage created in 2006.

Darhad men still sing a long ballad using an unidentified ancient language during the major rituals accompanied by a horse-head sacrificial instrument called the charig. The ballad is commonly called "the song of heaven" but no one knows its origin.

Even Khasbileg and his father, the only two men in the mausoleum who are able to read the characters, do not know their meaning. They are also reticent and reluctant to say much about this strange rite.

Khasbileg's father claims he cannot speak Mandarin, and his 16-year-old son, who looks energetic on the basketball court outside, suddenly falls silent during the interview.

They are from a family with one of highest positions among Darhad people. Since only men can be priests, Khasbileg has felt blessed to have a son.

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