Colorado Springs is a home rule municipality in, and the county seat of, El Paso County, Colorado, United States. It is the largest city in El Paso County, with a population of 478,961 at the 2020 United States Census, a 15.02% increase since 2010. Colorado Springs is the second-most populous city and the most extensive city in the state of Colorado, and the 40th-most populous city in the United States. It is the principal city of the Colorado Springs metropolitan area and the second-most prominent city of the Front Range Urban Corridor. It is located in east-central Colorado, on Fountain Creek, 70 miles (113 km) south of Denver.
Tongling, a prefecture-level city in Anhui Province, is located in the south-central part of Anhui Province and the lower reaches of the Yangtze River, with Hefei to the north, Chizhou to the south, Wuhu to the east and Anqing to the west, with a total area of 3008 square kilometers. Tongling gets its name from copper and flourishes with copper. it is known as "the ancient copper capital of China and the contemporary copper base". The history of copper mining began in the Shang and Zhou dynasties, flourished in the Han and Tang dynasties, and lasted for more than 3500 years. The first furnace of copper water and the first copper ingot in New China came from Tongling. The first copper industrial base was built in Tongling, and the first copper stock was issued in Tongling. In 2018, Tongling had jurisdiction over three municipal districts and one county, with a resident population of 1.629 million, achieving a GDP of 122.24 billion yuan, of which