The legends of Mustang are ones you can walk out upon.

Leave Lo Manthang and follow the river valley south for about fifteen kilometers, and there stands a monastery older than the entire royal city — Lo Gekar. It is built beneath wind-eroded red cliffs, prayer flags snapping in the valley wind; seen from afar, it is like an old seal wedged into the mountain's belly.

The locals say this seal was pressed down by a great siddha.

The legend begins with Guru Rinpoche.

It is said that after subduing the demon who wrought mischief in this place, the master, fearing its heart was not yet dead, built a monastery atop its heart to suppress it — and this is Lo Gekar. The name "Lo Gekar" means "white palace"; and in chapter sixty-two of the Pema Katang (The Testament of Padmasambhava), this tale of subjugation and temple-building is recorded in full, becoming the deepest annotation of the monastery.

What is stranger still is that the whole valley became an annotation of this legend:

The red cliffs (Dhakmar) were stained by demonic blood. Behind the monastery, ochre-red rock walls stretch like a curtain; the legend holds that this is the blood shed when the demon was subdued, reddening the entire cliff face.

The mani wall was transformed from the demon's intestines. On the road to Lo Gekar stands a mani wall hundreds of meters long beside Ghami village, carved all over with the Six-syllable Mantra; the legend holds that it is the demon's disemboweled intestines, transformed into this long wall of compassion.

The corpse of a single demon was turned by the great siddha into majesty filling the whole valley. This is the most common metaphor in Tibetan Buddhist legend — that affliction is precisely the field of practice.

Beyond legend, there is harder history.

Scholars hold that the founding of Lo Gekar can be traced back to the late eighth century, almost contemporaneous with Samye Monastery, the first in Tibet to possess the complete Three Jewels of Buddha, Dharma, and Sangha. If this is so, it is among the oldest extant monasteries of Mustang and indeed of the entire southern Himalaya.

It belongs to the Nyingma school — the most ancient branch of Tibetan Buddhism, which honors Guru Rinpoche as its founding master. The temple's principal image is of the Lotus-born master, and its walls are painted with majestic forms of bodhisattvas and Tara. The monastery's daily life is jointly tended by the monastics and laity of Marang village below: the monks practice here, the villagers provide their food and clothing, and an ancient shrine and a village have kept each other company for over a thousand years.

What is interesting is that this oldest Nyingma ancient shrine stands in contrast to the three Sakya temples within the city.

Inside Lo Manthang is the Sakya lineage established after the fifteenth century — royal temple, monastic school, and ceremonies, all in orderly array; in the river valley beyond the walls is the older Nyingma tradition — taking Guru Rinpoche as its source, grounded in tantric practice, with a stronger wildland air. One city, one monastery; one a rising lineage, one an ancient one — together, upon the same land, they have preserved both lifelines of Tibetan Buddhism.

For the pilgrim, these two need not be chosen between. First go to Lo Gekar and turn a prayer wheel atop the demon's heart; then return to Lo Manthang and light a lamp before the ancient Sakya murals — a single journey through Mustang, twofold fulfillment.

The Nyingma school upon which Lo Gekar depends is the most ancient branch of Tibetan Buddhism.

Nyingma, meaning "the ancient school," transmits the esoteric teachings of the early propagation period and honors Guru Rinpoche as its founding master. Guru Rinpoche was invited to Tibet in the eighth century and became renowned for subduing demons and spreading the esoteric teachings, later revered as the "Second Buddha." Legend has it that he subdued mountain gods and water spirits across Tibet and established sacred-site boundaries; the Mustang river valley where Lo Gekar stands is precisely a place where, by legend, he trod and left his mark of demon-subjugation.

The Nyingma school is grounded in tantric practice, valuing concealed treasures (terma), transmission, and oral instruction from master to ear. In borderlands where formal historical records are scarce, legend itself bears the function of history — the story of Guru Rinpoche's demon-subjugation is less a myth than the "consecration record" of how the ancient school's teachings took root in this land. Precisely for this reason, though far from the monastic colleges of Lhasa, Lo Gekar has always been regarded by Nyingma devotees as a sacred site personally blessed by Guru Rinpoche, its incense enduring unbroken for a thousand years.

What is carved on the mani wall, what is wound inside the prayer wheel, what is printed on the prayer flag — all is the same mantra: the Six-syllable Mantra.

"Om Mani Padme Hum" — the heart mantra of Avalokiteshvara, the most widely circulated mantra of Tibetan Buddhism. Each of the six syllables has meaning: Om is the primordial sound of the universe, Mani the jewel, Padme the lotus, Hum the perfection. Together, it invokes Avalokiteshvara, praying for the purification of the six realms and liberation from suffering to joy. Tibetans believe that to recite, write, or carve this mantra accrues merit equal to that of a scripture.

The mani walls of Mustang are the project of fixing this merit into stone. Slab upon slab carved with the mantra is layered up, stretching tens or even hundreds of meters, withstanding centuries of wind and rain, the carved strokes still clear. A passerby walks the wall clockwise and touches the stone with his hand, thus forming a connection with the myriad recitations upon it. By legend, the mani wall beyond Ghami village, transformed from the "demon's intestines," is the most spectacular stretch — the length of compassion measured precisely by the measure of the demon.

If one follows the river valley still deeper, there awaits another wonder that echoes the legend — the sky caves.

Among the cliffs of Upper Mustang are scattered caves carved into the rock face. These "sky caves" were sometimes dwellings of ancient people, sometimes meditation cells, suspended on cliffs hundreds of meters high, overlooking dry river valleys. From afar they resemble a honeycomb; up close they astonish — upon this land where almost nothing can be farmed, the ancients once survived, practiced, and endured by clinging to the cliff face in this way.

Here, legend and history are never clearly divided. Whether the red cliffs are demonic blood or iron rust, whether the sky caves are meditation cells or dwellings — there is no settled answer; yet what both pilgrims and travelers agree upon is that this land does possess a certain majesty beyond the everyday.

Today, Lo Gekar is still cared for by the villagers of Marang.

Every year, villagers and monks replace the temple's prayer flags. The old flags are torn into strips by the wind and scattered into the valley; the new flags snap and rise — upon the five-colored cloth, the same prayers are printed. The red cliffs remain red cliffs, the mani wall still stands in quiet, and the Six-syllable Mantra upon it has been polished bright by the palms of generation after generation of pilgrims.

Legend is not past tense; it lives in every circumambulation, every new flag, every carved stroke. The monastery built atop the demon's heart still breathes six hundred years on; and that long wall of compassion still recites the same mantra for every passerby.

The road to Lo Gekar is itself a practice.

Setting out from Lo Manthang, one first rides a horse down the river valley, then walks on foot through weathered rock and mani walls. The road is not long — about half a day's walking — yet it gives in full measure the plateau's fierce wind, dryness, and vastness. Along the way there are no villages, no shops, only prayer flags waiting in every hollow of the hills — blessings left by travelers of the past for those who come after.

The pilgrims say that only by walking this road does one truly arrive at Mustang. For the majesty within the city is for the eye, but this ancient shrine built atop the demon's heart must be reached on foot. The fatigue upon arrival is precisely the preparation before worship; stand beneath the red cliffs and look up, the wind snapping the prayer flags — and in that moment you understand: legend was never meant to be believed, but to be walked.

▶Watch furtherNEPAL: The Last Forbidden Kingdom on Earth | 8K Travel DocumentaryTrue Planet Explorer · Watch on YouTube

• Images: Gerd Eichmann (CC BY-SA 4.0, four photographs); Nishan Hitang (CC BY-SA 4.0)
• Video: NEPAL: The Last Forbidden Kingdom on Earth | 8K Travel Documentary · True Planet Explorer / YouTube

Return to Mustang · The Last Tibetan Kingdom.