Colorado (i /kɑləˈrɑːdoʊ/ or i /kɑləˈrædoʊ/) is a state that encompasses most of the Southern Rocky Mountains as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains. Colorado is part of the Mountain States, the Western United States, and the Southwestern United States.
Colorado is nicknamed the "Centennial State" because it was admitted to the Union as the 38th state in 1876, the centennial year of the United States Declaration of Independence. Colorado is bordered on the north by Wyoming and Nebraska, on the east by Nebraska and Kansas, on the south by Oklahoma and New Mexico, and on the west by Utah. The four states of Colorado, New Mexico, Arizona, and Utah meet at one common point known as the Four Corners. Colorado is one of only three U.S. states with no natural borders, the others being neighboring Wyoming and Utah.