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.
Mangshi, known as "Chuan Huan" in Dai language, is the capital of Dehong Dai Jingpo Autonomous Prefecture, Yunnan Province, people's Republic of China. It is located between 98 °05 Longitude 98 °44km east longitude and 24 °05km north latitude, about 71 km from east to west and 62 km from north to south, with a total area of 2987 square kilometers. Longling County is bordered by Longling County in the east and northeast, Ruili City in the southwest, Lianghe County and Longchuan County in the west and northwest across the Longchuan River, and the Republic of the Union of Myanmar in the south. It is the transportation hub leading to Ruili, Longchuan, Yingjiang and Lianghe, and it is also an important gateway for China to South and Southeast Asia. In ancient times, Mangshi was the territory of the Dai nationality, which is inhabited by the Dai, Han, Jingpo, Deang, Achang, Lisu and other ethnic groups, with a total population of 3949.