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.
Yangdong District belongs to Yangjiang City, Guangdong Province, bordering Yangchun City, Jiangcheng District and Enping City in the east, west and north respectively, and the South China Sea to the south. The coastline is more than 130km long and the land area is 1830 square kilometers. It is between 111 °42 degrees east longitude 112 °21 degrees east longitude and 22 degrees 15 'north latitude. In 2013, Yangdong District has jurisdiction over 11 towns (including 6 agricultural and forestry farms), a total of 171villages, 1688 village (resident) groups and 1488 natural villages. At the end of 2014, there were 498800 permanent residents and 502700 registered residents. In 2014, the region's gross domestic product (GDP) reached 25.808 billion yuan, an increase of 11.5% over the same period in 2013. Yangdong District is a national project pilot county with strong intellectual property rights.