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.
Tumen City is located in the east of Jilin Province, the eastern foot of Changbai Mountains and the lower reaches of the Tumen River, facing Wancheng County in North Korea, Hunchun City in the east, Yanji City in the west, Longjing City in the south and Wangqing County in the north. As of 2007, Tumen City has jurisdiction over 3 streets and 4 towns, with a total area of 1142.65 square kilometers. By the end of 2011, the total population of Tumen City was 126606. It is a multi-ethnic city dominated by the Korean nationality. The three lines of road, railway and shipping in Tumen City are all located in the "Golden Triangle" of Northeast Asia, which is an international transportation hub connecting the hinterland of Northeast China, North Korea and the Russian far East. On December 29, 2018, the sixth national unity and progress demonstration zone was named by the State ethnic Affairs Commission.