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.
Fogang County, Xiazhong County, Qingyuan City, Guangdong Province, located in the middle of Guangdong Province, on the edge of the Pearl River Delta, is a mountainous county, between longitude 113 °17028 "~ 113 °470042" east and latitude 23 °390057 "~ 24 °070015" north. It is adjacent to Conghua, Xinfeng, Yingde and Qingyuan City. The topography slopes from northeast to southwest, with low mountains, hills, valleys and plains crisscross, covering an area of 1295 square kilometers, with a registered population of 320700. There are many prehistoric cultural sites in Fogang, including the ancient kilns of the Western Zhou Dynasty, the bronze swords of the Spring and Autumn period, and the ancient roads of the Tang and Song dynasties. In 2014, the gross domestic product of Fogang County was 9.31 billion yuan, an increase of 12%, ranking among the highest in the city.