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.
Danyang, Zhenjiang City, Jiangsu Province, in charge of county-level cities, was called qu'an in ancient times, and got its name from the meaning of "Danfeng Chaoyang". Located in the Yangtze River Delta, located in the south of Jiangsu Province, belongs to the Taihu Lake basin. Danyang is one of the birthplaces of Wu culture. It was founded in the warring States period and is the hometown of Qi and Liang dynasties. Danyang culture belongs to Wu Yue culture, and the people of Danyang belong to the people of Jiangsu and Zhejiang provinces. Rivers crisscross in Danyang, 122 Provincial Highway, 312 National Highway, Shanghai-Nanjing Expressway, Zhendan Expressway, Beijing-Shanghai Railway, Beijing-Shanghai High-speed Railway, Shanghai-Nanjing Intercity Railway, Beijing-Hangzhou Grand Canal. In 1987, it was approved by the State Council to withdraw counties and build cities, and was listed as a coastal open city. Danyang is the world's largest lens production base, known as the "hometown of Chinese glasses" Meiji. The economic strength of Danyang ranks No. 1 in the comprehensive competitiveness of county-level cities in China in 2013.