The Front Range is a region in the US state of Colorado. It includes the range of the Rocky Mountains that gives it its name, as well as the Eastern Slope with communities in the eastern foothills of the mountains.
This region takes its name from possibly the best-known sub-range of the Rocky Mountains in the United States, so called because it was the first range encountered by historic settlers as they moved in from the east. However, the region also contains other mountains. In Colorado, the Rockies consist mainly of two broadly parallel ridge lines running diagonally across the state, with high mountain parks (valleys) between them, and it's convenient to treat both the mountains of the Front Range and also the Gore and Park Ranges (two of the "rear" ranges paralleling the Front Range) as part of the region, along with the intervening parks and a few cities in the foothills that some other sources call the Eastern Slope.
The mountains in this area, with a few exceptions, are generally not as high as the southern extension of the Rockies or the geologically distinct San Juan Mountains of Southwestern Colorado. However, they're still high enough to get serious winter weather, and winter sports are important here, with several world-famous ski resorts as well as Rocky Mountain National Park. East-west routes through the mountains are relatively few and far between, and generally go over high, rugged passes that may close for a while in the winter (and tax the cooling systems of passenger cars in the summer).
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 Northwestern Colorado, Eastern Plains (Colorado), Denver area, and even South Central Colorado and Southwestern Colorado.