Roots of royal lineage
Sonam Yontan, a PhD student at Xizang University specializing in the Lhagyari royal lineage, traces its origins to the ninth century, following the collapse of the Tubo kingdom.
A branch of the Tubo royal descendants found refuge in present-day Chusum county by the 13th century, where they rose to power as local rulers until Xizang's peaceful liberation in 1951.
In 1658, Depa Lhagyari, a local chieftain, was formally authorized by the local authorities to govern the Ae area, the broader historic name for Chusum. During his rule, the Ganden Lhatse Palace was constructed, marking the height of the lineage's local power and influence.
The renaming of Chusum in 1965 by the State Council further underscored the region's geographical heritage, referencing the "three rivers" — Karchu, Serchu and Gongpopuchu — that run through the area.
The Lhagyari Palaces illustrate the evolution of Tibetan palace architecture across three distinct phases.
The early phase includes remnants of walls and gates at the Tashi Chodzong Palace, which were built by local chieftain Lha Taley Namgyal in the late 15th century.
The middle phase is represented by the Ganden Lhatse Palace, built in the 17th century, and famous for its scale and strategic design.
The main surviving structures of the Ganden Lhatse Palace include a palace, warehouses and stables.
A later addition, constructed in the mid-20th century by local chieftain Lha Namgyal Gyatso, is the Summer Palace, designed as a quadrangular courtyard that embodies a blend of Han and Tibetan architectural styles.
"The architectural design, which integrates Tibetan styles with dougong (interlocking brackets) — a hallmark of Han craftsmanship — demonstrates the remarkable cultural synthesis of the time," says Sonam Yontan.
Like many Tibetan palaces, Ganden Lhatse was multifunctional, combining elements of a defensive stronghold, cultural center and trading hub.
Perched atop a small hill with steep cliffs to its north and east, the Ganden Lhatse Palace was naturally fortified, while stone walls protected its southern and western sides.
The palace includes servants' quarters, stables, a scripture library, and a ceremonial square (karshal in Tibetan). The square is paved with black and white pebbles arranged into auspicious Tibetan Buddhist symbols as well as elements inspired by the Great Wall.
Sonam Yontan notes that the pebble-paved square also had practical advantages, particularly the effective drainage system during rainfall — a testament to the ingenuity of its designers.
"In the past, locals called the area karshal — referring to the square, because the palace square was so well known," he says.