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.
Lu County is the lower jurisdiction county of Luzhou City, Sichuan Province, which is located in the south of Sichuan Basin, between longitude 105 °10 °50 "~ 105 °45 °30" east longitude and latitude 28 °54 °40 "~ 29 °20 °00" north. Lu County is bordered by Yongchuan District of Chongqing City and Hejiang County of Luzhou City in the east, Longmatan District and Jiangyang District of Luzhou City in the south, Fushun County of Zigong City in the west, and Rongchang District of Chongqing City and Longchang City of Neijiang City in the north. Lu County is a major national cultural relic county, with 6 key cultural relics protection units such as Longnaoqiao and Song Tombs in Luxian County. It is a national construction and labor base county, a national model county with double support, a national health city, and one of the top 100 counties in the western region. On February 2, 2019, it was rated as a county-level national advanced unit of traditional Chinese medicine by the State Administration of traditional Chinese Medicine.