The State of Wyoming is a state in the western region of the United States of America. The majority of the state is dominated by the mountain ranges and rangelands of the Rocky Mountain West, while the easternmost section of the state is a high altitude prairie region known as the High Plains. The tenth largest U.S. state by size, Wyoming is the least populous, with a U.S. Census estimated population of 522,830 in 2007, a 5.9% increase since 2000. The capital and the most populous city of Wyoming is Cheyenne.