Eastern Plains (Colorado)
Roughly speaking, this region is bounded on the:
Region boundaries in Colorado are indistinct, and sometimes contentious. If you're looking for a destination/attraction that you think should be in this region, but can't find it, check the pages for Denver Area, South Central Colorado and Front Range.
This is the largest, but most sparsely populated, of Colorado's regions. It occupies the easternmost third of the state, stretching from Nebraska in the north to New Mexico in the south. The only substantial city in the region is Pueblo, on Interstate 25 south of Denver (which is in its own region) and Colorado Springs (treated with the south central region).
Most visitors to Colorado view this area as something one simply drives through quickly, en route to Denver and the mountains. However, there are some points of cultural/historic interest connected with the Santa Fe Trail, which passed through the southern part of the region. The National Grasslands throughout the region preserve wild lands that provide a reminder of what the Great Plains were like before the arrival of settlers from the east.
For more information, see Wikitravel's article Rail travel in the United States.
During the winter, heavy ice and snow are a major concern, which can make driving difficult and slow going. Always check the weather and road conditions  before heading out. Even on a clear winter's day, make sure your vehicle's wiper fluid reservoir is full. The Colorado Department of Transportation (CDOT)  spreads both sand and magnesium chloride on the roads, which makes for an impenetrable, gluey mess on your windshield.