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.
Changxing County, which belongs to Huzhou City, Zhejiang Province, is located in the north of Zhejiang Province, the Hangjiahu Plain in the Yangtze River Delta and the southwest bank of Taihu Lake. It is bordered by Anji County, Wuxing District, Huzhou City, Guangde County, Anhui Province and Yixing City, Jiangsu Province. It is between 30 °43 miles north latitude 31 °11 miles north and 119 °33 miles east longitude, covering a total area of 1430 square kilometers. Changxing is called the Great Wall in ancient times. During the period of the struggle for hegemony between Wu and Yue in the Spring and Autumn period (514-495 BC), King he Lu sent his brother to build the city two miles southeast of the pheasant city. Because the city is long and narrow, it is named the Great Wall, which has a history of more than 2500 years. By 2018, Changxing County had jurisdiction over 4 streets, 9 towns and 2 townships, with a total registered population of 636400, realizing the regional gross domestic product.