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.
Yimen County is located in the central and western part of Yunnan Province, northwest of Yuxi City, connected with Anning City and Jinning District in the east, Eshan in the south, across the Luzhe River in the west and Shuangbai, and bordered by Lufeng County and Anning City in the north. It belongs to Yuxi City. The southeast is 146 kilometers away from Hongta District of Yuxi City, and 94 kilometers northeast from the provincial capital Kunming. The high-grade highway with a mileage of 43 kilometers can reach Kunming and Chuxiong from the county seat. The county has a distance of 44 kilometers from east to west and 57 kilometers from north to south, with a total area of 1571 square kilometers, ranking fourth in Yuxi City. The total population is 177110 (2010). The government is stationed in Longquan Town. Yimen Longquan National Forest Park, a national forest park approved by the State Forestry Administration in 1992.