Mountain States

region of the United States

The Mountain States (also known as the Mountain West or the Interior West) form one of the nine geographic subregions of the United States that are officially recognized by the United States Census Bureau. It is a subregion of the Western United States.

Regional definitions vary from source to source. The states shown in dark red are always included, while the striped states (Arizona and New Mexico) are usually considered part of the same region called the Mountain States.

The Mountain States usually include: Arizona, Colorado, Idaho, Montana, Nevada, New Mexico, Utah, and Wyoming.

The words "Mountain States" generally refer to the U.S. States which cover the U.S. Rocky Mountains. These are oriented north-south through parts of the states of Montana, Idaho, Wyoming, Colorado, Utah, and New Mexico. Arizona and Nevada, as well as other parts of Utah and New Mexico, have other smaller mountain ranges and scattered mountains located in them as well. Sometimes, the Trans-Pecos area of West Texas is considered part of the region. The land area of the eight states together is some 855,767 square miles (2,216,426 square kilometers).