Meri Puensum is the name given to the three small mountains that rise up sharply to the west from the floor of Haa valley. They are a presence wherever you find yourself in the valley, and for centuries they have been venerated as the abode of three principal deities in the Vajrayana Buddhist pantheon. Farthest north is Jampelyang (Manjushri), in the middle is Chana Dorjee (Vajrapani), and Chenrezi (Avalokiteshvara) is southernmost.
This practice of seeing mountains and valleys as inhabited by deities harkens back to Haa's pre-Buddhist, animist past. It was common then to sacrifice animals as propitiation to the local deities. In the 8th century, the great Buddhist saint Guru Padmasambhava subdued these deities and bound them by oath as guardians of the Buddhist tradition. Still to this day, Haaps perform ceremonies — usually sans sacrifice — in homage to Ap Chandu, the guardian deity of the valley.
And the mountains do have a certain presence. As the sun drops behind the Meri Puensum on clear days it creates dramatic light shows, casting long ethereal rays into the valley in sequence before disappearing into dusk. It's stunning and gives the entire valley a feeling of blessedness. Locals believe that these brother mountains maintain peace in the valley and continually bless it. Once you come here, you may believe it too.