You should be talking about Yan Liang

As far back as the Qin and Han Dynasties, Yan Liang occupied an important position in politics, economy and military affairs, and was the seat of the ancient oak Yangcheng, a famous historical city in China. Qin Xiaogong used Shang Yang's political reform here to lay a solid foundation for unifying the world. Liu bang took this as the base camp, thus boarding Jiuding Supreme.

Yanliang is a modern city. Yanliang is an administrative region directly under the jurisdiction of Xi' an. The area is located at the northeast end of the city, which looks like a lying cow, with its head in the east and its tail in the west, with Jingshan in the north and Weishui in the south. The total area of the region is 244 square kilometers, the urban planning area is 61 square kilometers and the built-up area is 21.28 square kilometers. Now it has jurisdiction over Hualu Sub-district Office, Fenghuang Sub-district Office, Xinxing Sub-district Office, Beitun Sub-district Office, Zhenxing Sub-district Office, Guanshan Town and Hewutun Town, belonging to sub-prefecture level areas. There are 16 ethnic groups, including Han, Hui, Manchu and Mongolian, with a total population of 251,111. Convenient traffic conditions have been brought into Xi 'an half-hour economic circle. The service function is perfect, and the indicators such as the reliability of power supply and water supply, the rate of natural gas entering households, the per capita housing area of urban residents, the ownership rate of urban family private cars, and the average wage of urban employees are among the highest in all districts and counties in the province. There are two four-star hotels, more than 21 large-scale comprehensive shopping malls and catering enterprises, with smooth logistics and active consumption. The city has a beautiful environment and is named as a provincial garden city, a sanitary city and a safe area. Four fully functional city squares, the newly built Yanliang Park, the aviation exhibition hall, the first garbage recycling factory in the northwest and the aviation science and technology corridor to be built soon make Yanliang have a strong modern urban atmosphere.

Yanliang is a famous aviation city, and Yanliang is a world-renowned China airplane city. In the early days of the founding of the People's Republic of China, Yanliang was listed as a national key aviation industrial base, which integrates the design, manufacture, identification and flight test of large and medium-sized aircraft for military and civilian use. It is not only an aircraft industrial base, but also an aviation scientific research base and an aircraft identification flight test base. Xi 'an Aircraft Industry Company is the largest aircraft manufacturer in China. China Flight Test Research Institute is the only aviation equipment flight test research center in China, ranking first in Asia in scale, and also the top comprehensive aircraft appraisal flight test base in the world. Xi 'an Aircraft Design Institute is the only large and medium-sized aircraft design and research institution in China. Over the years, the three aviation companies have cooperated closely and achieved a series of brilliant results. Flying Leopard, xinzhou 61 and ARJ21 are developed and produced here. There are 25,111 aviation scientific and technical personnel in the area, more than 111 experts who have made outstanding contributions, and those with college education or above account for 1.2 of the urban population. Yanliang Aviation High-tech Industrial Base has a strong development momentum, with 126 registered enterprises at present, and a number of major projects such as China Flight Strength Test and Research Center and 81,111-ton die forging hydraulic press are under construction.