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.
Gaoqing County, which belongs to Zibo City, Shandong Province, is located in the Lubei Plain and the northern end of Zibo City, with a total area of 831 square kilometers. As of 2018, Gaoqing County has a total registered population of 369900; there are 25 ethnic minorities such as Miao, WA, Yi, Zhuang, Hui, Manchu and Mongolian in Gaoqing County. As of 2018, Gaoqing County has jurisdiction over 2 streets and 7 towns, and the county government is stationed at 81 Huanghe Road, Tianzhen Street. In 37 (1948) April, Gaoyuan, Qingcheng two counties merged into Gaoqing County, Li CPC Bohai Office. On January 1, 1990, Gaoqing County was assigned to Zibo City. Gaoqing County is located in the south of North China Plain depression (Ⅰ structure) and Jiyang depression (Ⅱ structure). It is a part of a large sedimentary basin. The terrain is high in the west and low in the east, tilting from northwest to southeast.