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.
Guazhou County, which belongs to Jiuquan City, Gansu Province, is located at the western end of the Hexi Corridor in Gansu Province, Yumen City, the oil city in the east, Dunhuang City in the west, the Mongolian Autonomous County in Subei in the north and south, and Hami in the northwest. Since ancient times, it has been the transportation hub of east to west and the merchant town of the ancient Silk Road. Guazhou County is 185km long from east to west and 220km wide from north to south, covering an area of 24100 square kilometers. Guazhou County has jurisdiction over 5 towns, 10 townships and 73 administrative villages. at the end of 2011, Guazhou County had a resident population of 149500, including 21 ethnic groups such as Han, Hui, Mongolian and Tibetan, and a minority population of 25000 (2011). Guazhou County has 4 national cultural relics protection units and 16 provincial cultural relics protection units. In 2011, the GDP of Guazhou County reached (G