Great white gypsum sand dunes cover 275 square miles of the Chihuahuan Desert. There are four hiking trails including one that is wheelchair accessible. We loved the one-mile Big Dune Nature Trail with guide map that explains the plant life along the trail.
But the big treat was the 4.6-mile hike to Alkali Flat, the lake basin where this all began 250 million years ago. The trail is extremely well marked leading across giant pure white dunes in the Heart of the Sands. If you are near Alamagordo (15 miles away)or Las Cruces (50 miles away), this is well worth a stop long enough to make this hike. It took us 1.5 hours, but it says that it takes up to three hours for those not used to hiking. JUST DO IT!