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.
Zhidan County, which belongs to Yan'an City, Shaanxi Province, is located in the hilly and gully region of the Loess Plateau in the north of Shaanxi Province, connected with Ansai in the east, Wuqi County and Jingbian County in the northwest, Ganquan County and Fuxian County in the southeast, and Heshui County and Huachi County in Gansu Province in the southwest. Between longitude 108o 11mm 56 "- 109o 3m 48" east and latitude 36o 21m 23 "- 37o 11m 47" north, with a total area of 3781 square km. Zhidan County, formerly known as Baoan County, was renamed Zhidan County in June of 1936 in memory of General Liu Zhidan, a "mass leader and national hero". In July of the 25th year of the people's Republic of China (1936), the Central people's Government of the Chinese Soviet Union held the capital Zhidan. The CPC Central Committee and Chairman Mao fought and lived here for more than six months, known as the Central Committee of the Communist Party of China.