Early every spring, between the 8th and 10th days of the second lunar month, well-dressed crowds from across eastern Bhutan and as far afield as Tawang in India descend on Gom Kora (also known as Gomphu Kora) for the ancient temple's annual tsechu.
Located in a rocky valley 23km (14 miles) north of Trashigang, this historic temple owes its existence to Guru Rinpoche, who meditated in a cave at the base of the sacred black rock in the eighth century. Legend tells how, when the Guru's meditation was disturbed by a demon, the two fought fiercely, leaving imprints on the boulder's surface that are revered today.
During the festival, a ceaseless stream of worshippers walk kora (ritual clockwise circuits) around Gom Kora lhakhang and the black boulder behind it in a vigil lasting into the night. Locals believe this to be an optimal time for meeting future life partners; many young people circumambulate the monastery late at night, singing prayers and looking for potential wives or husbands.
Nearby, masked monks whirl in the Dance of Wrathful Deities, blessing the onlookers with their steps, and makeshift villages of stalls sell toys and sweets beneath a sea of blue tarpaulins.
The excitement builds through a series of masked chham dances to the unfurling of a ritual thongdrol that blesses all who lay eyes on it.