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.
Yanshan County belongs to Cangzhou City, Hebei Province, with a total area of 800 square kilometers, located in the southeast of Cangzhou City, facing the Bohai Sea to the east, Beijing and Tianjin to the north and Shandong to the south. It is the center of the "two provinces" (Hebei Province and Shandong Province) and "three cities" (Cangzhou, Dezhou and Binzhou). It is known as "Jilu Hub" and "Beijing-Tianjin Portal". It is 120 kilometers away from Tianjin, 220 kilometers from Beijing, 160 kilometers from Jinan, 50 kilometers away from Huanghua Port and 110 kilometers away from Tianjin Port. You can go to sea in half an hour and board the plane in one hour. Yanhuang Railway, New Beijing-Shanghai Expressway, 205 National Highway and other national trunk lines run through the county, and the three major railway lines of Beijing-Kowloon Railway, Beijing-Shanghai Railway (passenger dedicated line) and Shuohuang Railway pass by the major traffic arteries such as Shihuang Expressway and Tianjin-Shantou Expressway. The total area of the county is 800 square kilometers, with cultivated land.