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.
Qingshui County, under the jurisdiction of Tianshui City, Gansu Province, is located in the southeast of Gansu Province, northeast of Tianshui City, Niutou River Basin, a tributary of the Weihe River on the north bank of Longshan, southwest of Longshan; Longxian County, Baoji in the east, wheat accumulation area in the south, Qinan County in the west, and Zhangjiachuan Hui Autonomous County in the north; it is located in the transitional zone from Longshan Mountain to Longxi Loess Plateau, with temperate continental monsoon climate; it has jurisdiction over 15 towns and 3 townships with a total area of 2012 square kilometers. The total population in 2018 is 332364. Qingshui was called Shangfu in ancient times and got the name of the county from "four Notes of Qingquan". It is the birthplace of Huangdi Xuanyuan, the first ancestor of Chinese humanities, the birthplace of Qin unified China, and the hometown of Zhao Chongguo in the Western Han Dynasty. Prehistoric culture, pre-Qin culture, Han and Tang culture, Song (Jin) and Yuan culture accumulation; the territory has been identified by the State Administration of Cultural relics as "Wei and Jin ancient city" and "not"