Yushu remains nomadic culture's permanent home. Erik Nilsson explores the iconic settlement in the extreme elevations of yak country.

Yushu's legacy as a bastion of Tibetan culture is literally written in stone. That is, the high-altitude prefecture in Qinghai province hosts the world's largest collection of mani (prayer) stones-an estimated 2.5 billion-some as small as pebbles, some as big as boulders.

Pilgrims purchase stones carved with scriptures or sacred images and place them on the Seng-ze Gyanak Mani Wall.

Craftspeople carve the inscriptions on-site and take custom orders, such as prayers for deceased relatives. The sounds of their chisels striking the rocks echo off the mountains, providing percussion that accompanies the droning chants of the devout and tinkling of bells slung around the necks of yaks that clip-clop through the site.

Pilgrims spin prayer wheels beneath prayer flags as they circle the prayer stones, which cover an area roughly the size of a city block.

They also burn incense, as the smoke is believed to carry their prayers to heaven, and juniper branches, whose fragrance is believed to cleanse the soul.

The first stones were laid in 1715, and people have since continued to enlarge the walls day by day, stone by stone, as if building a colossal anthill.

Yushu's magnitude 7.1 quake in 2010 scattered the mantras like the shards of a dropped porcelain vase. But they were quickly put back in place by the faithful.

The wall is a superlative attraction but far from the only place that makes Yushu an ideal destination to engage Tibetan culture.

Princess Wencheng Temple

Sutras are also carved into the rock of the cliff that hosts the Princess Wenchang Temple-a small compound that plays a big role in local history.

Qinghai's oldest Buddhist temple is dedicated to Wencheng's month-long stay in Yushu as she traveled from today's Xi'an, Shaanxi province, to Lhasa in the seventh century. The royal is particularly venerated for converting her husband, Tibetan king Songtsen Gampo, to Buddhism.

Countless prayer flags cocoon the mountain and span the gorge like a massive multicolored spider web. Monks chant scriptures in a cave halfway up the cliff.

Upon entering the main courtyard beneath, visitors scoop water sanctified for Buddha in cupped hands and use it to wash their hair. The buildings display statues of Songtsen Gampo and the Buddha of primordial wisdom, Nampa Namse, as well as precious stones, sacred seashells and ancient artworks.

Dondrubling Monastery

Dondrubling Monastery is literally a peak attraction in Yushu.

It crowns a hill that offers panoramas of Jeykundo city, the prefecture's seat, which was built around the holy site after it was completed in 1398 and-like the temple itself-rebuilt in traditional style following the 2010 quake.

The massive complex hosts red walls, golden rooftops and an even more colorful interior.

Caterpillar fungus market

Caterpillar fungus is so venerated as a traditional cure-all that Jeykundo hosts an entire market devoted entirely to the parasite that's endemic to the Qinghai-Tibet Plateau and Himalayas.

The organism infests ghost moth caterpillars buried in the grasslands above 3,500 meters. It digests the larva from within, mummifying the insect's body, until it sprouts from its head like a unicorn horn.

Its purported medicinal applications, which range from impotence to cancer, plus its rareness mean a kilogram sells for anywhere from a few hundred to hundreds of thousands of yuan. It's often brewed in tea or steeped in alcohol, especially antelope-blood liquor.

Earthquake memorial

The Gesar Hotel's ruins have been preserved to commemorate the disaster that razed many of Jeykundo's buildings and killed about 2,700 people throughout the prefecture.

An adjacent museum displays photos of rescue operations, relief work and before-and-after shots of the cityscape.

The memorial hosts such items as a clock frozen at the moment the temblor struck.

This timeless timepiece serves as an eternal reminder of that instant, while the surrounding city testifies to Yushu's past and future as a place of prominence in Tibetan culture.