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.
Zhen'an County is one of the buildings under the jurisdiction of Shangluo City, Shaanxi Province. Located in southeastern Shaanxi Province, the southern foot of Qinling Mountains, southwest of Shangluo City, Han River tributaries Qianyou River and the middle reaches of Xunhe River, 175.5 kilometers from east to west, 72.5 kilometers wide from north to south, with a total area of 3477 square kilometers. The terrain is high in the northwest, low in the southeast, with many mountains and ditches and little arable land. It is an earth-rocky mountain area with "nine mountains and half water and half divided fields". Zhenan County is a national science popularization experimental county, a national medical reform pilot county, a garden city in Shaanxi Province, and a sanitary county in Shaanxi Province. Zhenan chestnut is famous for its large color, sweet and delicious, full grains, rich nutrition and unique quality, and is known as "the hometown of Chinese chestnut". Since ancient times, Xi'an is the main road to Ankang, is the natural link between Shaanxi and Hubei, known as "Qin Chu throat". 2019