China has invested 280 million yuan (about 45.5 million U.S. dollars) to protect the relics of the ancient Koguryo Kingdom since it was inscribed onto the UNESCO World Heritage List ten years ago.

Dating back some 2,000 years, the cultural heritage property in Ji'an, a small town in Northeast China's Jilin province, consists of the cities of Wunu Mountain, Guonei and Wandu Mountain, as well as King Haotaiwang Stele and 38 tombs for both Kogurgo Kings and noblemen.

Dong Feng, director of the Ji'an Administration of Cultural Heritage, said in an interview with Xinhua that the money had been used to support more than 20 projects, including tomb mural preservation, preventing Kogurgo King's tomb from leakage, protecting the mountain town of Wandushan and constructing Ji'an Museum.

More than 1,000 cultural relics are on display in the 6,400-square-meter museum, said Dong.

Jin Xudong, chief of the Jilin Provincial Administration of Cultural Heritage who led the archaeological work, said the Koguryo heritage was China's first success in grand heritage site protection.

Hailed as an outstanding example of the evolution of piled-stone and earthen tomb construction, the site represents human creative genius in the Middle Age, according to the evaluation of the World Heritage Committee.

Many tourists visit Ji'an each year. In 2013, tourism generated 20 percent of the city's total gross domestic product, official statistics showed.