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.
Yan'an City, referred to as "Yan", the prefecture-level city of Shaanxi Province, is the first mausoleum in the world-the mausoleum of the first ancestor of the Chinese nation, the mausoleum of the Yellow Emperor: the site of the Yellow Emperor Mausoleum, is a sacred place for the nation, a sacred place for the Chinese revolution, and the first batch of famous national historical and cultural cities announced by the State Council. Yan'an is located in the north of Shaanxi Province, in the middle reaches of the Yellow River, in the south-central part of the Loess Plateau, and 371 kilometers north of the provincial capital Xi'an. It is connected to Yulin in the north, Xianyang, Tongchuan and Weinan in Guanzhong to the south, Linfen and Luliang in Shanxi to the east, and Qingyang in Gansu to the west. With a total area of 37037 square kilometers, it is known as "Sanqin key, five-way flap throat". Yan'an, known as Fushi and Yanzhou, is an important birthplace of the Chinese nation and the ancestor of humanities.