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.
Shimian County, which belongs to Ya'an City, Sichuan Province, is located in the eastern part of the Hengduan Mountains on the Qinghai-Tibet Plateau, the middle reaches of the Dadu River, the southwest of Ya'an City, and its geographical coordinates are 101 °55 in longitude and 102 °34 in longitude and 29 °32 in latitude. Shimian County has a total area of 2678 square kilometers. It belongs to the mountain climate with mid-latitude subtropical monsoon climate as the base belt, with concentrated summer rain, more night rain, less storms and no autumn continuous rain. Shimian County has jurisdiction over 1 street, 1 town, 5 townships and 10 ethnic townships, and the county government is stationed in the streets of Mian City. As of 2018, the total registered population of the county is 128800. In the thirteenth year of Daoguang of the Qing Dynasty (1833), the soil was changed and the land of the fourteen fortresses was placed in Shunhe Township. At the end of the Qing Dynasty, it was "ready to establish a constitution". Shunhe became an autonomous township of its own, all on the north bank.