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.
Shuangjiang gets its name from the intersection of Lancang River and Xiaohei River in the southeast of the county, which belongs to Lincang City, Yunnan Province. The county covers an area of 2165.03 square kilometers, and has jurisdiction over 4 townships, 2 towns, 72 villages, 3 communities, Mengku overseas Chinese Management District and Shuangjiang Farm Management Committee. As of 2013, the total population is 170000. In 2012, Shuangjiang County completed an annual GDP of 2.3 billion yuan. Shuangjiang is the hometown of multi-ethnic cultures in China, and it is the only multi-ethnic autonomous county in China composed of Lahu, WA, Bulang and Dai nationalities. Shuangjiang is the native place of Mengku Daye tea in China. Mengku Daye tea, which originated in Shuangjiang, was twice evaluated as an improved variety of Chinese traditional tea by the National Tea Variety Committee in the 1960s and 1980s. Shuangjiang is the green pearl on the Tropic of Cancer, which runs through Shuangjiang County.