Chokorgyel exists because of Lhamo La-tso, a small oval lake no more than two square kilometers in size, perched at roughly 5,000 meters above sea level. The monastery sits four hours' hike below it. Since the time of Gendun Gyatso, the 2nd Dalai Lama, who founded a hermitage here in 1509 and formalized the reincarnation system, senior monks have trekked to this lake to seek guidance on choosing the next Dalai and Panchen Lamas. They meditate at the water's edge, waiting for visions to appear on its surface. Palden Lhamo, the female guardian spirit of the lake, is said to have promised the 1st Dalai Lama that she would protect the reincarnation lineage. The monastery below became the essential halting place for these pilgrimages, eventually growing to house 500 monks.

The monastery's geography reads like a mandala. Mount Zhidag to the north is the "white" mountain, home to Shidrak, an ancient Bonpo protector of the earth. At its foot sits the Dalai Lamas' residence; higher up, remains of a temple preserve the footprint of Damchen Choje, the Dharma Protector. To the south rises Shridevi, the "blue" mountain of the Protectress Palden Lhamo, where a dundro -- a sky burial site -- looks out over the valley. The eastern peak, Mount Begtse, is the "red" residence of Protector Begtse, a deity imported by the Gelugpa school from Mongolia. On its slope sits Nyingsaka, an interdenominational gompa whose name combines syllables from Nyingma, Sakya, and Kagyu -- three of Tibet's four major Buddhist traditions sharing a single roof.

The monastery's original builders shaped it as an inverted triangle, deliberately mirroring its setting at the confluence of three rivers. This geometry represented the conjunction of water, earth, and fire, as well as the female principle of Palden Lhamo. The ruins still visible today -- massive walls enclosing two monastic colleges called dratsangs and two large temples -- trace that triangular footprint. The Lukhang, temple of the Serpent Protectors, was built over the 2nd Dalai Lama's original hermitage. Legend holds that red eagles, the kyungka or garudas, constructed it. The main temple, the Tsuklakhang, once housed a large statue of Mipam Gompo dating to the monastery's founding. Damaged murals still cling to its walls, faded but legible to those who know what to look for.

Chokorgyel has been destroyed more than once. In 1718, Dzungar Mongols severely damaged the complex; the Regent Kangchene ordered an immediate rebuild. But nothing ancient could have survived to 1959, when Chinese forces arrived. The Cultural Revolution proved more thorough than any Mongol raid. Workers removed every piece of wood from the buildings, leaving only stone walls exposed to wind and snow. The 2nd Dalai Lama's meditation cave was destroyed, though his footprint pressed into stone has survived, embedded in a mani wall. South of the monastery walls, the Shinje Melong -- the Mirror of the Lord of Death -- also endures: a polished grey granite stone traditionally used to read horoscopes and conduct rain-making ceremonies, smooth as a dark window onto another world.

Today Chokorgyel is neither abandoned nor restored. The main hall functions again, and a handful of monks live among the ruins at 4,500 meters. The path to Lhamo La-tso still climbs from here, 115 kilometers northeast of Tsetang and 160 kilometers southeast of Lhasa. At the center of the complex, a small pillar engraved with sutras and a Buddhist swastika marks a point that has been considered sacred for over five hundred years. The pillar stands among roofless walls, in a valley where three rivers still converge, beneath three mountains still assigned their ancient colors. What the monastery once was -- a thriving community of 500 monks guarding the most consequential lake in Tibetan Buddhism -- it is not. What it still is, at minimum, is the only path to the place where the next incarnation might be seen.