Don't Forget the Fun of Getting There
You're going to be spending at least 4 days round trip just on the drive to and from Colorado, so that will make up a large portion of your vacation. By adding a day or two on each segment you can explore the gorgeous country between home and Colorado, as well as break up the long drive into more enjoyable pieces with restful stops in between. Just as a first cut, you might want to look at a northern route via I-15 and I-70 through Las Vegas, Zion, Bryce and Arches, and a southern route via I-8, I-17, US-89, and US-160 past the Grand Canyon, Monument Valley, and Mesa Verde.
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