From Denver, Colorado Springs, or Pueblo, the most common route is south on I-25 to Walsenburg, west on US 160, north on State Highway 150. For a more mountainous drive from Denver (same mileage as the I-25 route), you may also take US 285 south, then State Highway 17 south, then County Lane 6 east from Mosca.
Photographing the Great Sand Dunes in Colorado can have its challenges. It's a long walk to get into the dunes and you often can get lost trying to find the best landscape to photograph. On this day I arrived too late to make it further into the dunes. However, sometimes the clouds can make for even better pictures.