The Rockies also extend into northern New Mexico and north-central Utah (both however are considered part of the Southwest region). The Canadian Rockies are located in the provinces of Alberta and British Columbia in Canada.
The Rocky Mountains are huge or better put long, ranging 3,000 mi (4828 km) from British Columbia to New Mexico, and reach as high as 14,440 ft (4,401 m) above sea level (Mt Elbert in Colorado). For the past four centuries, visitors have come to encounter from the long flat plains in the east to the shocking and iconic wall of the Front Range just east of the continental divide—the Cheyenne aptly called the mountains, "Rock on the Horizon."
The largest and most popular entry point into the region is Denver, which is one of North America's principal rail and flight hubs. Domestic flights to the other major cities in the region, like Cheyenne, Boise, Billings, or Jackson, should be easy to find from any American hub airport.
Route 25 is the major north-south highway, leading up from New Mexico, while I-70, I-80, and I-90/94 are the major east-west highways. Be aware that passes do get closed due to inclement weather (snow) in winter months, in particular I-70 is prone to this. Bus routes exist, mostly through Greyhound, but given the long distances, flying is often cheaper than paying for gas and bus fares on the road.
Getting around the Rocky Mountains can be tough. Mountain passes freeze in the winter, as you might expect, and many roads are risky, if not impassable under heavy snow. Moreover, you'll run through more gas per mile in the high altitudes. Flying is often a very good alternative in the winter, since Denver offers flights straight to ski slopes off in the mountains, as well as to virtually all the cities in the region.
During the warmer months, however, driving becomes a ''great'' way to explore the region. Some of the most spectacular drives in the country are located here among the high mountains and endless wilderness. It can also be the ''only'' way to get to destinations off the beaten path, since, as you might expect, there's not a lot of public transportation in this vast and lightly populated section of the country.
The sights here are not urban in the slightest. With the exception of Denver, there are no really large metropolis. Wyoming has less people than Alaska, and is proudly Amreica's least populated state! Colorado boasts the hightest overall elevation in the USA. Come here to admire the wildlife and spectacular vistas in the National Parks. Many of North America's most renowned parks are here, from the geysers of Yellowstone, to the glaciers in Montana, to elk and bighorn sheep wandering among the high peaks of Rocky Mountain National Park. Black and Grizly bears, wild cats, and buffalo are also found in the region.
Also of interest are the old mining and cowboy frontier towns that once comprised of most of the region's population. Many old gold mine towns have transformed themselves into a tourist economy destination, with tours leading right down into old gold mines. The cowboy towns remain, however, and that way of life has not yet died out. A good example is Leadville, Colorado.
Outdoor adventure is the entree on the Rocky Mountain platter. There's wonderful hiking just about everywhere, from the ravines in the plains in the east, to canyons in the west, to the high mountain trails along the Rocky Mountains spine. Trails are managed by the National Park service, State Park services, and National Forest and Grasslands services. Camping is widely available throughout all the wilderness regions of the Rocky Mountain states. Outside of the National Parks, it's not even regulated—you can just drive into any national forest and pitch a tent wherever your fancy. Hunting and fishing is regulated heavily by the Department of Fish and Wildlife, to protect local fauna from overhunting, but the activities are widely practiced, and you'll have some beautiful areas in which to enjoy them.
The biggest draw to the region, without a doubt, is the fantastic downhill winter sports. Ski resorts like Aspen and Vail rank among the world's finest, and are priced accordingly. But there's a wealth of other more affordable, and still fantastic options. The ski season in the Rockies starts early in the late Fall, and lasts long until the late Spring. The snow quality is magnificent, and the weather usually surprises with how warm it can be.
Sporting events are not quite so widely available as you would find in other parts of the country (simply because there are fewer big cities here), but Denver makes up for that, with a lively sports culture, and one great football team, the Denver Broncos. If you're interested in the cowboy culture of the Rockies, look for a rodeo—especially away from the ski resorts and the biggest national parks, they're not half as touristy as you might suspect.
Drinking, on the other hand, is a time honored activity in the Rockies, and it is done well. Colorado in particular is home to an enormous quantity of microbreweries, and you'll never be in want of good local beer throughout the region. Liquor laws are very lax compared to the rest of the country (in general, there are fewer laws out here), and you can often pick up some beers at a drive thru window!
You're very unlikely to be the victim of crime in the Rockies, but you do need to be vigilant about safety in the wilderness. Don't get too close to buffalo, who will charge your car if provoked (and the bulls can smash a car in two if they want to). Don't leave any food in smellable or reachable containers, and hang your food in a bear bag far enough from your tent where a nosy bear wouldn't check both out in the same outing. The cold in the winter is the deadliest force around—make certain that someone knows where you are when you venture out, and always research the conditions in advance and prepare for them adequately. Make a point of registering with the local park service when embarking on a multi-day hike, so they know you're out there, and have an idea of how to rescue you if that becomes necessary.
The Rockies don't stop here, and there's an extraordinary wealth of high mountain trekking opportunities just west in Utah. And to the north are the beautiful Canadian Rockies.
If you're looking for more National Parks, but with a change of pace, head south into the Southwest for iconic red rock and desert parks.