Gesar

Gesar of Ling was a legendary king in Tibetan and Central Asian mythology. Tibetan communities in India, Mongolia, Buryat, Bhutan and Nepal have various versions of the epic of Gesar. The Chinese compilation so far of just its Tibetan versions has filled some 120 volumes, more than one million verses, divided into 29 "chapters". It is considered the world's longest epic.

Biography
Gesar of Ling was born from Gog bza, a beautiful naga princess captured from a neighboring tribe, and Seng blon, one of the respected elders of the Kingdom of Ling. Jealous that this child would become a threat to his power, Gesar's evil uncle Todong tried to kill him several times as a child. Gesar then tricks Todong to hold a horse race to determine the rightful ruler of Ling. Confident that he will win, Todong agrees and loses to Gesar, who marries the princess, Sechan Dugmo. Later, Gesar wages a war on Lutzen, the demon king of the North. Lutzen is protected by an army of demons, enslaved humans and enslaved gods. Gesar conspires with Queen Dummo, Lutzen's human wife, to defeat the demon. Dummo then poisons Gesar, and he forgets his memory and becomes her prisoner and "lover" for years. When he remembers his identity, his real wife, Sechan Dugmo, has been taken by the evil King of Hor. Gesar then embarks on an epic quest to rescue her.

Location in Tibet
In most Tibetan versions, Ling is located in eastern Tibet (Tibetan: Mdo khams), often between the 'Bri (Yangtze) and rDza (Yalong) rivers, which is where the historical kingdom of Lingtsang (Tibetan: Gling tshang) existed until the twentieth century.

Kyeri Trowo Tobgyal Khar, an abandoned Tibetan fortress in eastern Changthang, is said to have been built by Trowo Tobgyal, a minister of Dud Lutzen (bDud klu-btsan), the region’s ruler and one of the primary villains in the King Gesar epic. The fortress consists of just a single sandstone and limestone structure (7.5 m x 4 m), which has been leveled to its revetment and lower walls. That Kyeri Trowo Tobgyal Khar is an archaic monument is indicated by its epic association with the non-Buddhist ruler of the region, the lack of a contemporary permanent water source in the vicinity, the extremely high and isolated aspect of the site, and typological parallels with the so-called Mon castles of the western Changthang.