The relic was discovered in 2003 during the construction of a new National Assembly building. The digging revealed an abundance of artefacts and structures from the Ly, Tran, Le and Nguyen dynasties. The structures were built on top of each other and dated from the 10th to the 19th centuries.

According to experts, the relic meets all UNESCO requirements for being a World Cultural Heritage site.

The Secretariat of the World Heritage Committee is scheduled to give opinions on the dossier on November 15, 2008 so that Vietnam will finalise and submit the official version to the committee before February 1, 2009.

The committee will convene its annual meeting in June or July 2009 to consider nominations for the title.