Mountain states
One of nine U.S. Census divisions, encompassing the Rocky Mountains.
The Mountain states, also known as the Mountain West or the Interior West, form one of the nine geographic divisions of the United States officially recognized by the United States Census Bureau. They are a subregion of the Western United States, comprising Arizona, Colorado, Idaho, Montana, Nevada, New Mexico, Utah, and Wyoming. The region is defined by the presence of the U.S. Rocky Mountains, which run north-south through portions of Montana, Idaho, Wyoming, Colorado, Utah, and New Mexico, with other smaller mountain ranges and scattered mountains in Arizona and Nevada.
- States included
- Arizona, Colorado, Idaho, Montana, Nevada, New Mexico, Utah, Wyoming
- Largest city
- Phoenix
- Fastest-growing region
- Yes, in the United States
- Highest mean elevation
- Among all 50 U.S. states
- Primary time zone
- Mountain Time (except Nevada and Idaho Panhandle, which observe Pacific Time)
Lore & Background
The Mountain states are considered to include Arizona, Colorado, Idaho, Montana, Nevada, New Mexico, Utah, and Wyoming. The words 'Mountain states' generally refer to the U.S. states which encompass the U.S. Rocky Mountains. These are oriented north-south through portions 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.
Reader's Guide
The Mountain states are one of the largest and most diverse regions in the United States. Its physical geography ranges from some of the highest mountain peaks in the continental United States to large desert lands and rolling plains in the eastern portion of the region. The Great Basin Desert is located in almost all of Nevada, western Utah, and southern Idaho. Portions of the Mojave Desert are located in southern Nevada, the Sonoran Desert in much of Arizona, and the Chihuahuan Desert in most of southwestern and southern New Mexico. The High Plains, a portion of the Great Plains, lie in the far-eastern portions of the region. The climate is generally semi-arid or arid, with alpine climates in the mountains. The region is the fastest-growing in the United States, with Utah, Idaho, Nevada, Colorado, and Arizona ranking among the fastest-growing states. The Phoenix metropolitan area is the most populous metropolitan area, followed by Denver, Las Vegas, and Salt Lake City.
Did You Know?
- The Mountain states are one of nine geographic divisions officially recognized by the United States Census Bureau.
- Phoenix is the largest city in the Mountain states.
- Daylight saving time is not observed in Arizona, except for lands within the Navajo Nation.
Frequently Asked Questions
What exactly are the "Mountain states" in U.S. geography?
It is one of the nine official geographic divisions the U.S. Census Bureau uses to organize the country. The division sits within the broader Western United States and takes its name from the Rocky Mountain range that threads through its core.
What time zone do people in the Mountain states live in?
Most of the region follows Mountain Time, but Nevada and the northern panhandle of Idaho are the exception, observing Pacific Time instead.
Why do geographers and fans find the Mountain states region notable?
It holds the highest average elevation of any U.S. state grouping and is currently the fastest-growing region in the country. Its landscape is dominated by the north-south spine of the Rockies plus smaller ranges scattered through Arizona and Nevada.
What is the largest city in the Mountain states?
Phoenix, Arizona, holds that title as the most populous city across all eight states in the division.
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