Trashigang, “The Jewel of the East”, traverses the easternmost edges of the kingdom, dodging up to the point of the Indian state of Arunachal Pradesh. It is the country’s widest district, with an elevation varying from 600 m to over 4000 m. Bhutan’s largest tributary, Drangme Chhu, glides through this region. It sets Trashigang town on a panoramic hilltop and was previously a bustling business center for vendors seeking to barter their valuables in Tibet. Now, it is the confluence of the East-West highway with highway links to Samdrup Jongkhar and the Indian state of Assam. Trashigang town is likewise the key marketplace for the semi-nomadic communities of Merak and Sakteng, whose strange style of clothing stays out from the traditional Bhutanese Gho and Kira.
Trashigang Dzong, or fortress, was built in 1659 by the third Druk Desi Chögyal Mingyur Tenpa to defend against Tibetan invaders. Because of its altitude invading armies remarked that "it is not a dzong on the ground, it is in the sky". An ancient Lhakhang or temple in the district, known for its rock garden, contains a sacred footprint said to be either that of Guru Rimpoche or that of a khandroma (angel).