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.
Xichong County, which belongs to Nanchong City, Sichuan Province, is located in the north-east of Sichuan Basin, the southwest of Nanchong City, Shunqing District in the east, Jialing District in the south, Yanting County in Mianyang City, Pengxi County and Shehong County in Suining City in the west, and Nanbu County in the north. The total area is 1106.59 square kilometers, and the county seat is 25 kilometers away from Nanchong city in the north. There is Xichong Mountain in ancient times, so it is named Xichong, which is the ecological back garden and satellite city of Nanchong. Belongs to the subtropical humid monsoon climate zone, shallow hilly landform, the average annual temperature is 16.9 ℃, the annual rainfall is 980.8 mm, the average elevation is 361.2 meters, the frost-free period is more than 300 days, the four seasons are distinct, and the climate is mild. As of 2019, Xichong County has jurisdiction over 16 towns, 5 townships and 2 streets. By the end of 2017, the total population of Xichong County was 605900.