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.
Liupanshui City is a prefecture-level city in Guizhou Province. Liupanshui City is located in Wumeng Mountain area of western Guizhou, with an annual average temperature of 15 ℃, an average temperature of 19.7 ℃ in summer and an average temperature of 3 ℃ in winter. With a cool, comfortable, moist, fresh climate and moderate ultraviolet radiation, it has been awarded the title of "cool capital of China" by the Chinese Meteorological Association and is the only city in the country named after its climatic characteristics. During the Spring and Autumn period, Liupanshui was a dependency of Yelang; during the warring States period, the city was a dependency of Yelang, which entered the farming era and reflected the characteristics of slave production relations due to the use of metal tools; after Qin unified China, it was a dependency of Hanyang County, Ba County. Liupanshui is located in the junction of Yunnan and Guizhou provinces, the watershed in the upper reaches of the Yangtze and Pearl Rivers, and both sides of the Nanpanjiang and Beipanjiang basins, which is rich in mineral resources. Traffic extends in all directions and is important in the southwest.