San Antonio (/ˌsæn ænˈtoʊnioʊ/ SAN an-TOH-nee-oh; Spanish for "Saint Anthony"), officially the City of San Antonio, is a city in Texas, United States. The city is the seventh-most populous in the United States, the second-largest in the Southern United States, and the second-most populous in Texas. It is the 12th most-populous city in North America, with 1,434,625 residents in 2020.
Founded as a Spanish mission and colonial outpost in 1718, the city in 1731 became the first chartered civil settlement in what is now present-day Texas. The area was then part of the Spanish Empire. From 1821 to 1836, it was part of the Mexican Republic. It is the oldest municipality in Texas, having celebrated its 300th anniversary on May 1, 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.