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.
Runan County, which belongs to Zhumadian City, Henan Province, faces Pingyu County in the east, Shangcai County in the north, Zhengyang County in the south and Linyi City in the west. It is between 114o 21km east longitude, 114o 53m east longitude and 33o 00km north latitude, with a total area of 1475 square kilometers. Runan is located in the Huaibei Plain with a history of nearly 2000 years. Han Gaozu bought Runan County, which was already a land and water wharf connecting the north and south of the Central Plains. There are more than 280 cultural sites in China, which have been approved as open counties by the State Council of China and designated as famous historical and cultural cities by the Henan provincial government. As of 2018, Runan County has jurisdiction over 4 streets, 12 towns and 2 townships. By the end of 2017, Runan County had a resident population of 658000, with a GDP of 19.61 billion yuan, of which