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.
Turpan, a prefecture-level city under the jurisdiction of Xinjiang Uygur Autonomous region, located in the middle of the autonomous region, is an olive-shaped intermountain basin in the east of Tianshan, surrounded by mountains on all sides, belonging to a typical continental warm temperate desert climate; it has jurisdiction over one district and two counties with a total area of 69713 square kilometers and a total population of 637300 in 2017. Located in the hinterland of Eurasia, Turpan is the gateway to Urumqi and an important transportation hub for the new Silk Road and Eurasian Continental Bridge. Lanxin Railway and Nanjiang Railway meet here and form a three-dimensional transportation system of "highway, railway and aviation" with Turpan airport and G30 line. It has the location and convenient transportation advantages of "connecting north and south, east to west, west to east", and realizes the regional economic integration of Wutu.