The Kansas City metropolitan area is a bi-state metropolitan area anchored by Kansas City, Missouri. Its 14 counties straddle the border between the U.S. states of Missouri (9 counties) and Kansas (5 counties). With 8,472 square miles (21,940 km2) and a population of more than 2.2 million people, it is the second-largest metropolitan area centered in Missouri (after Greater St. Louis) and is the largest metropolitan area in Kansas, though Wichita is the largest metropolitan area centered in Kansas. Alongside Kansas City, Missouri, these are the suburbs with populations above 100,000: Overland Park, Kansas; Kansas City, Kansas; Olathe, Kansas; Independence, Missouri; and Lee's Summit, Missouri.
Changning County, which belongs to Yibin City, Sichuan Province, is located in the southern edge of Sichuan Basin, in the heart of Yibin City, between longitude 10444 °22 "~ 105 °03 °30" east longitude 28 °15 °18 "~ 28 °470048", about 60 kilometers from north to south, 30 kilometers from east to west, an area of 1000.2 square kilometers, forest coverage of 62.8%, and the content of negative oxygen ions in the air can reach up to 47000 per cubic centimeter (Qidonggou). It is a famous hometown of longevity. As of August 24, 2019, Changning County has jurisdiction over 13 towns with a total population of 460400 (2018). There are 9 ethnic groups, including Han, Miao and Yi, among which 28 are over 100 years old, the oldest is 112 years old, and the number of people over 90 years old has reached 1075.