With a history of more than 2,300 years, the Langzhong ancient city in Nanchong, Sichuan Province, is one of the four most famous ancient cities in China. Known as the birthplace of Chinese Spring Festival culture, it is said to be the hometown of the Western Han Dynasty (202-25 BC) astronomer Luo Xiahong, who set the first month of spring as the beginning of the year in his Tai Chu calendar. This practice was continued in successive dynasties, cementing the custom of celebrating the Spring Festival. The Langzhong ancient city, now covering an area of around 2 square kilometers, is home to over 100 well-preserved residential buildings from the Ming and Qing dynasties (1368-1911), as well as dozens of ancient alleyways and streets.