The first excavation of the main rampart (Đèo Bụt site) started on 16 July. Led by Nguyễn Tiến Đông of the Institute of Archaeology in cooperation with the Hà Tĩnh province department of culture, the research aimed to test the hypothesis (drawn from a reading of the court chronicles) that this system of defence was built by the Trịnh Lords during the seventeenth-century wars fought by the lords of the North and South.

 fieldwork