I went to White Sands National Monument in New Mexico. The area is covered by white sand dunes and interesting creatures like white lizards. The dunes are made of gypsum that washed down out of the nearby mountains into salty lakes. The area is in a basin that does not drain to a river or ocean. As the water evaporates it leaves the gypsum behind which is then pushed around by the wind and breaks down into grains of sand.
I went for a hike in the sand dunes on a portion of the Alkali Flat Trail, but the scenery all pretty much looked the same after a few dunes so I turned back. They have the trail marked so you can find your way back, similar to how cross country ski trails are marked in the winter up north.
After lunch I took off and started going west again.