Phoenix (/ˈfiːnɪks/ FEE-niks; Navajo: Hoozdo; Spanish: Fénix or Fínix,[citation needed] Walapai: Banyà:nyuwá) is the capital and most populous city of the U.S. state
of Arizona, with 1,608,139 residents as of 2020. It is the fifth-most populous city in the United States, and the only U.S. state capital with a population of more than one million residents.
Phoenix is the anchor of the Phoenix metropolitan area, also known as the Valley of the Sun, which in turn is part of the Salt River Valley. The metropolitan area is the 11th largest by population in the United States, with approximately 4.85 million people as of 2020. Phoenix, the seat of Maricopa County, has the largest area of all cities in Arizona, with an area of 517.9 square miles (1,341 km2), and is also the 11th largest city by area in the United States. It is the largest metropolitan area, both by population and size, of the Arizona Sun Corridor megaregion.
Yanchang County, which belongs to Yan'an City, Shaanxi Province, is located in the north of Shaanxi Province and east of Yan'an City. It is 73 kilometers from east to west and 55 kilometers from north to south, with a total area of 2368.7 square kilometers. The early human activities in Yanchang County can be traced back to the Neolithic Age. Western Jin Tai began two years (266 years), established the establishment of the county. Several changes, to the second year of Tang Guangde (764), because the Yanhe River from the county from west to east into the Yellow River, the name Yanchang County, still in use. The terrain tilts from northwest to southeast, high in the north and south, low in the middle, showing a valley peak type. Is a warm temperate dry continental monsoon climate, spring, summer, autumn and winter four distinct seasons, cold, warm, dry and wet. By 2018, Yanchang County had jurisdiction over one street and seven towns with a resident population of 128500, achieving a GDP of 54.077.