San Jose,[A] officially San José (/ˌsæn hoʊˈzeɪ, -ˈseɪ/; Spanish: [saŋ xoˈse]; Spanish for 'Saint Joseph'),[B] is a major city in the U.S. state of California that is the cultural, financial, and political center of Silicon Valley and largest city in Northern California by both population and area. With a 2020 population of 1,013,240, it is the most populous city in both the Bay Area and the San Jose-San Francisco-Oakland Combined Statistical Area, which contain 7.7 million and 9.7 million people respectively, the third-most populous city in California (after Los Angeles and San Diego and ahead of San Francisco), and the tenth-most populous in the United States. Located in the center of the Santa Clara Valley on the southern shore of San Francisco Bay, San Jose covers an area of 179.97 sq mi (466.1 km2). San Jose is the county seat of Santa Clara County and the main component of the San Jose–Sunnyvale–Santa Clara Metropolitan Statistical Area, with an estimated population of around two million residents in 2018.
Jiayuguan, known as "the first male pass in the world", is located in the middle of the narrowest valley 5 kilometers west of Jiayuguan City, Gansu Province. the city walls on both sides of the pass cross the Gobi Desert, the suspended Great Wall of Montenegro in the north and the first pier in the south. it is the westernmost pass of the Ming Great Wall. it was once known as Hexi throat in history, because of its dangerous topography and majestic architecture, it is known as the chain key of the border. Jiayuguan is the traffic fortress of the ancient "Silk Road" and one of the three wonders of the Great Wall of China (Shanhaiguan in the east, Zhenbeitai in the middle and Jiayuguan in the west). Jiayuguan was built in the fifth year of Hongwu of the Ming Dynasty (1372). It is composed of inner city, outer city, Luocheng, Wengcheng, trench and the north and south wings of the Great Wall, with a total length of about 60 kilometers. The platform, pier and fortress of the Great Wall are dotted with three lines of defense, namely, the inner city, the outer city and the moat.