Co Thanh tomb, so-called "So" tomb is the place where Lord Nguyen Phuc Luan (1733-1765) - the father of Emperor Gia Long was buried. Located about 11km from Hue city center, the architecture is a part of Cu Chanh village, Thuy Bang commune, Hue city, Thua Thien Hue province.
As found in royal documents, Nguyen dynasty showed concern to Co Thanh tomb to pay tribute to ancestors. Nguyen Emperors and royal families held offering ceremony at Co Thanh tomb at the end of the year or tomb sweeping festival. Those protecting the architecture and soldiers were given rewards. Particularly, Nguyen Emperor had the tomb renovated regularly, therefore, this tomb still can be found today.
The tomb was surrounded by huge wall and covered a large area, however, the majority of the structure was destroyed by war. The main part where the square three-storey tomb was situated still remains.
Having existed for over 200 years, the tomb is actually not as unique and grand as other tombs constructed under Nguyen dynasty. However, Co Thanh tomb reminds people of the gloomy history of Vietnam in late 18th century and sad stories about life of Lord Nguyen Phuc Luan.
Co Thanh tomb was recognized as a national relic on decision 874-QD/BVHTT on May 12th, 1997 of the Ministry of Culture and Information.