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.
Tuanfeng County, which belongs to Huanggang City, Hubei Province, is located in the eastern part of Hubei Province. It is located on the south wing of the Dabie Mountains, facing the Bahe River to the east and raising water and Shahe to the west, and adjacent to Ezhou City, Xinzhou District of Wuhan City, Huangzhou District of Huanggang City, Xishui County, Luotian County and Macheng City, between longitude 114o 47mm east longitude, 30 °35km north latitude, 44 km east-west horizontal width, 38 km north-south vertical length, with a total area of 833.11 square kilometers. Tuanfeng has a long history, which began in the Tang Dynasty and formed a market in the Song Dynasty. In history, the ancient town Tuanfeng has always been a place where soldiers must compete. Cao Cao once deployed troops in Wulin, and Zhu Yuanzhang defeated Chen Youren here. Always prosperous commerce, merchants gathered in the Ming and Qing dynasties, and the market was prosperous, and it was one of the important commercial ports along the Yangtze River. The group style gave birth to the "one" of the Party.