San Diego (/ˌsæn diˈeɪɡoʊ/ SAN dee-AY-goh, Spanish: [san ˈdjeɣo]; Spanish for 'Saint Didacus') is a city on the Pacific Ocean coast of Southern California located immediately adjacent to the Mexico–United States border. With a 2020 population of 1,386,932, it is the eighth most populous city in the United States and the seat of San Diego County, the fifth most populous county in the United States, with 3,338,330 estimated residents as of 2019. The city is known for its mild year-round climate, natural deep-water harbor, extensive beaches and parks, long association with the United States Navy, and recent emergence as a healthcare and biotechnology development center. San Diego is the second largest city in the state of California, after Los Angeles.
Zhongshan County, under the jurisdiction of Hezhou City, Guangxi Zhuang Autonomous region, is located in the northeast of Guangxi, surrounded by arched mountains, with high terrain, rich in light and heat, and abundant rainfall; it has a total area of 1472 square kilometers and has jurisdiction over 10 towns and 2 Yao townships; the total population in 2017 is 448500. Zhongshan County is located at the junction of Southwest China and South China Economic Zone. National Highway 323, Guiwu Expressway, Guiyang-Guangzhou Railway and Yonghe Expressway run through the county. It is the most convenient sea passage for southwestern China to enter Guangdong, Hong Kong and Macao eastward. Local specialties are Yingjia kohlrabi, Zhongshan tribute mandarin, safflower yuba, high-quality rice and so on. The main tourist attractions (spots) are Hetang Shili Gallery, Huashan Scenic spot, Zhongshan Yuanfeng, Shilong Shiqiao, Longdao ancient folk houses and so on. In October 2017, it was selected into the first batch of national experimental and demonstration areas for sustainable agricultural development; 1