Nearly 35,000 wood blocks used for rudimentary printing during the Nguyen dynasty era (1802-1945) are preserved at the National Archives Centre IV in the tourist city of Da Lat.

The blocks are made of pieces of wood with Chinese or ancient Vietnamese letters carved in reverse.

The Nguyen dynasty's epigraphs created using them include history, socio-political, military, legislative, educational and artistic works, said Pham Thi Hue, director of the centre.

Apart from their historical value, the blocks are also artistically and technically precious since they mark the beginning and development of wood-block carving and printing in Vietnam , she added.

In 2009 UNESCO recognised the Nguyen dynasty's wooden blocks as a memory of the world, a programme launched to preserve and disseminate valuable archival holdings and library collections world-wide.

In 1960 more than 50,000 of the Nguyen dynasty blocks had been stored in the royal city of Hue before they were moved to Da Lat.

After 1975, many of them were lost.

Hue 's centre has worked to find and collect the blocks, many of which were in the possession of individuals around the country.

Tran Van Phong, a Da Lat resident, recently presented one to the centre after discovering its significance.

It belongs to the 66th volume of the series titled Dai Nam Thuc Luc Chinh Bien De Tam Ky (Royal Annals of Great Vietnam), which is recognised as precious ancient national book.

Phong said the block had been in his family's possession for years and handed down as an heirloom./.