Group 1 - The 9th Cultural and Natural Heritage Day in China will be held on June 14, 2025, with the main venue in Changsha, Hunan, where a series of classic cases on cultural relic protection and revitalization will be released [1] - The Laosi City site, located in Yongshun County along the Lingxi River, is recognized as Hunan's first World Cultural Heritage site, serving as a "living fossil" of the Tusi system and a witness to ethnic cultural exchange and integration [6][9] - The core area of the Laosi City site covers approximately 250,000 square meters, featuring multiple functional zones such as palace, government office, residential, and burial areas, with over ten thousand artifacts unearthed, providing valuable material for studying the ancient Tusi system and ethnic culture [9] Group 2 - The ancient city walls of Laosi City were constructed using a mixture of lime, glutinous rice, tung oil, and cotton, making them exceptionally sturdy and well-preserved to this day, symbolizing prosperity and good fortune [11] - To revitalize cultural heritage, Laosi City is actively promoting the integration of culture and tourism, transforming the site into a popular cultural tourism landmark [13]