Colorado

Each September, Colorado heralds a gold rush, one that blankets mountainsides and meadows in bright yellow foliage. The quaking aspens—so named because the leaves' long stalks render them sensitive to the slightest breeze—have a short peak color window, but since the white-barked trees come into full golden radiance at different times around the state, mobility is rewarded. Driving trips are one good option; train journeys another. For instance, Pikes Peak Cog Railway takes passengers through aspen forests on its way to 14,110 feet above sea level. Among deciduous trees, aspens are superlative: What looks like a forest is usually a single tree with hundreds or thousands of runners sent out to create sprouts of itself, making aspens among the largest life forms on the planet. Colorado is easy on the wallet this time of year, too: It was recently named one of SmarterTravel's top five bargain destinations for fall.

Where is your favorite place to admire the changing of the aspen in fall?