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.
Lanzhou, referred to as "Lanzhou" or "Gao", or Jincheng in ancient times, is the capital of Gansu Province, an important industrial base and comprehensive transportation hub in northwest China approved by the State Council, one of the important central cities in the western region, and an important node city of the Silk Road Economic Belt. By 2018, the city had jurisdiction over five districts and three counties, with a total area of 13100 square kilometers, a built-up area of 321.75 square kilometers, a resident population of 3.7536 million, an urban population of 3.0415 million, and a urbanization rate of 81.03%. Lanzhou is located in northwest China and the central part of Gansu Province. It is located in the geometric center of the land territory of the Chinese mainland. It is a comprehensive transportation hub of railways, highways and aviation in Northwest China. It is also the headquarters of the army organs in the western theater of the Chinese people's Liberation Army. It is also the new Eurasian continental bridge.