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.
Kaifeng, known as Bianzhou and Bianliang in ancient times, is a prefecture-level city in Henan Province. It is a cultural tourism city approved by the State Council and one of the central cities in the core area of the Central Plains urban agglomeration. By 2018, the city had jurisdiction over five districts and four counties, with a total area of 6266 square kilometers, a built-up area of 129.93 square kilometers, a resident population of 4.5649 million, and an urban population of 2.23 million, with a urbanization rate of 48.9%. Kaifeng is located in the hinterland of the Central Plains, the shore of the Yellow River, adjacent to Zhengzhou in the west. Kaifeng Free Trade Zone is one of the three major free trade pilot zones in China (Henan). It is the first batch of famous national historical and cultural cities with a history of more than 4100 years, including Xia Dynasty, Wei State in the warring States period, Hou Liang, Hou Jin, Hou Han, Hou Zhou and Song Dynasty in the five dynasties.