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.
Dunhua City, which belongs to Yanbian Korean Autonomous Prefecture, is the "west gate" of Yanbian Prefecture. Located in the eastern mountainous area of Jilin Province, the hinterland of Changbai Mountain, one of the node cities in the pilot area of Changjitu development and opening up, it is the largest county-level city in Jilin Province and an important transportation hub in Jilin Province. it connects Jilin and Heilongjiang provinces, four districts and nine counties and cities. Dunhua is known as the "century-old county, the ancient capital of thousands of years". It is the capital of the Bohai Sea in the Tang Dynasty, Aodong City in the Ming and Qing dynasties, and the birthplace of the Manchu royal family. In 1881, a county was established and named Dunhua; in 1958, the county under the jurisdiction of the province was assigned to Yanbian Korean Autonomous Prefecture, and the county was withdrawn to set up a city in 1985. Dunhua is an excellent tourist city, a national sanitary city, a national garden city, a national model city with double support, a model collective of national unity and progress, and the name of Chinese solid wood products.