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.
Hanshan County, which belongs to Maanshan City, Anhui Province, is located on the north bank of the middle and lower reaches of the Yangtze River, east-central Anhui and the shore of Chaohu Lake. The total area is 1047 square kilometers. Hanshan has a history of more than 1300 years since the county was bought in the sixth year of Tang Wude (623). It is the hometown of Wu Chu in the Spring and Autumn period, known as Wu Tou and Chuwei. There are many tourist attractions in Hanshan, mainly Taihu Mountain and Huayang Cave, two national AAA scenic spots. By 2018, Hanshan County had 8 towns and 3 parks with a resident population of 395000, achieving a regional gross domestic product (GDP) of 17.358 billion yuan, of which the added value of the primary industry was 2.032 billion yuan, the secondary industry was 8.465 billion yuan, the tertiary industry was 6.86 billion yuan, and the proportion of the three industries was 11.749.