Initially built as a monastery by Zhabrung''s great grandfather Lama Ngagi Wangchuk in 1549 and later in 1646 Zhabdrung Ngawang Namgyel built it into Dzong. It is the largest Dzong in Bhutan with a circumference of more than 1.5 km. Now the Dzong houses the administrative seat to the Bumthang district.