Daga Dzong, formerly known as Daga Trashiyangtse Dzong is a fortress in Dagana district in Southern Bhutan. Daga Dzong is one of the oldest dzongs in Bhutan.
The name Daga Dzong is derived from two sources; Darkala, which comes from the province’s guardian deity Jomo Darkala and Darkanang (The Realm of White Prayer Flags) from Dudjom Jigdrol Yeshey Dorji, a great Buddhist master. The Daga Dzong was traditionally the stronghold of the Daga Penlop, who held the rank of cabinet minister under the Desi (temporal ruler) system of government introduced by Zhabdrung Ngawang Namgyel in 1651. The dzong was constructed in the year 1651 and is seen as a significant heritage place because of its glorious history. Druk Namgyel was commanded to build the dzong under the order of Zhabdrung Ngawang Namgyel to defend the area from the southern states, present day Assam and West Bengal. Due to the defensive functions of the dzong, the fortress occupies a ridge overlooking the valley.
It is presently the headquarters for the Dagana district administration and monastic body. Among other sacred relics, the dzong houses a buffalo horn measuring about 4’5”. The horn is believed to have been discovered by Daga Penlop Tempa Thinley in the early 16th century.
Ever since Daga Dzong was built in 1651, no major renovation has been carried out until 2012.