Great Sand Dunes National Park Feature

Dune climbing: Trek through the 30 square mi of main dunes in this landlocked dune field.

Unrivaled diversity: You can see eight completely different life zones in this park, ranging from salty wetlands and lush forests to parched sand sheet and frozen alpine peaks, all in a single day.

Bounty of bison: Take a ride around the west end of the park, where more than 2,000 bison roam in the grasslands and wetlands.

Aspens in autumn: Take a hike—or, if you've got a high-clearance four-wheel-drive vehicle and good driving skills, take the rough road—up to Medano Pass during fall foliage season when the aspens turn gold.

Vigorous hikes: Pack a picnic lunch and climb up to High Dune, followed by the more strenuous stretch over to Star Dune. Or tackle the dramatic Music Pass Trail, which takes you to the tree line and covers 3½ mi (and 2,000 feet in elevation change) each way.