I visited the Great Sand Dunes NP in 2001.It was then National Monument.It was a hot sunny afternoon and I was hungry too.I was driving to Mesa Verde NP. All of sudden, there appeared tall sand dunes in the midst of seemingly endless vast San Juan Valley. I thought they were truly mirage or my hypoglycemia. I revisited in the middle of September this year and found the place is full of miracles with intriguing multi faces depending on time, weather, and seasons etc.