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.
Nanchong, also known as "Guocheng, Silk Capital", is a prefecture-level city in Sichuan Province and the second most populous city in Sichuan. Provincial economic deputy central city, one of the central cities of Chengdu-Chongqing economic circle, important node city of "Belt and Road Initiative" strategy, regional central city of northeast Sichuan, excellent tourist city of China, national garden city, national clean energy demonstration city, one of the top 200 cities with dense belt of southern Suigang cities and towns, and one of the top 200 charming cities with Chinese characteristics. Nanchong is located in the northeast of Sichuan Province and the middle reaches of the Jialing River, which is named because it is located in the south of the country; it has jurisdiction over 3 districts (Shunqing District, Gaoping District, Jialing District), 5 counties (Yingshan County, Xichong County, Nanbu County, Pengan County, Yilong County), escrow one county-level city (Langzhong City), household registration population 7.5902 million (2014), and an area of 12479.96k square.