The Ho Dynasty Citadel in the central province of Thanh Hoa has attracted an increasing number of tourists since it was recognised as a World Cultural Heritage site last year.

A total of 11,000 visitors came to the site in the first six months of this year, a sharp increase compared to the figure of 2011, at 16,000.

The main attraction is the gigantic stone citadel built six centuries ago, which is the only one built entirely of stone in Vietnam . It has remained almost intact through ups and downs in history.

Blocks of stone used to build the walls of the citadel had an average dimension of 2.2m x 1.5m x 1.2m and weighed an average 20-25 tonnes. Some of them were 4.2m x 1.7m x 1.5m and 5.1m x 1m x 1.2m with the biggest weighing up to 26.7 tonnes. The larger blocks were laid under the smaller ones. This was seen as an achievement in construction engineering, using such large stone blocks that have never been found in other imperial cities.

The rock site in An Tôn Mountain, Vĩnh Yên commune, Vĩnh Lộc district, which supplied stone for the building of the citadel, and the Nam Giao worship platform, which were built of only small blocks measuring 40cm-50cm x 30cm or 40cm x 20cm-30cm, also draw many tourists.

The UNESCO will officially present the site with a certificate of its heritage status, this month.

Thanh Hoa province plans to conduct deeper research on the Ho Dynasty Citadel, while investing more in the management, preservation and development of the site. The province hopes that the site will receive 35,000 visitors a year by 2015.-VNA