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.
Dachuan District, under the jurisdiction of Dazhou City, Sichuan Province, is located in the south of the main urban area of Dazhou City, and is located in the connecting zone of parallel ridges and valleys in the east of Sichuan Basin, hilly areas in the middle of the basin and low mountain areas around the basin. The general trend of topography is high in the northwest and low in the southeast, belonging to the mid-subtropical monsoon humid climate type; it has jurisdiction over 2 streets, 29 towns and 25 townships, with a total area of 2245 square kilometers, with a total population of 1.118 million at the end of 2017. Dachuan District has a long history and profound cultural heritage. There are a large number of historical celebrities, such as Chun Shenjun, one of the four princes of the warring States, Sima Yuan Zhen of Tongzhou in the Tang Dynasty, Wei Chengfang of the Ministry of officials in the Ming Dynasty, Tang Zhen, an outstanding thinker in the Qing Dynasty, and so on. Unique location and convenient transportation. Dachuan, as the joint of Sichuan, Chongqing, Hubei and Shaanxi, is located in the radiation center of the four major cities of Chengdu, Chongqing, Xi'an and Wuhan.