In a solemn atmosphere, the parliamentary leader and a delegation of senior officials expressed their gratitude to the great contributions of the emperors who established the state of Dai Co Viet.
On the occasion, Chairman Hue planted memorial trees at Hoa Lu, a special national site.
The activity took place as part of the series of events to mark the 50th anniversary of the Convention concerning the Protection of the World Cultural and Natural Heritage, to be held in Ninh Binh Province on September 6.
