Ho Citadel

Ho Citadel (Thanh Nha Ho) is a 14th-century stone citadel located in Vinh Loc District, Thanh Hoa Province, about 45 km northwest of Thanh Hoa City. Built in 1397 by Ho Quy Ly as the capital of the Dai Ngu kingdom, it is notable for its massive limestone walls constructed without mortar. Inscribed as a UNESCO World Heritage Site in 2011, it represents a unique example of Vietnamese citadel architecture and urban planning.

Visitors can expect a large rectangular walled enclosure built from huge limestone blocks with four arched stone gates, the south gate being the most intact and monumental. Inside is a largely open grassy area with archaeological remains, an exhibition house displaying artifacts, stone tools and models of the citadel, and walking paths connecting the gates. The citadel is set in a flat rural landscape surrounded by rice fields, villages and limestone hills, with interpretive panels explaining construction techniques.

Built in 1397 under the order of Ho Quy Ly, a prominent official of the Tran Dynasty who later founded the Ho Dynasty. It served as the capital of Dai Ngu from 1398 to 1407. Constructed in just three months using large limestone blocks fitted without mortar, it is considered a unique example of Vietnamese military architecture and represents a period of reform and centralization in Vietnamese history.

Inscribed as a UNESCO World Heritage Site in 2011 for its outstanding example of a Southeast Asian citadel built according to feng shui principles. It reflects Vietnamese cultural identity, traditional construction techniques, and urban planning that harmonizes architecture with the natural landscape of mountains and rivers.