The Biggest Dunes in the United States
When you think about sand dunes, you either think about the Mesquite Flats or Sahara Desert. However, there is an overlooked stretch of hilltop sand that happens to be the largest and tallest in the United States, Kelso Dunes. It is located 3 hours away from OC/LA near the town of Baker, San Bernardino County, California. The drive isn't so bad until you exit the freeway. That's when you enter a 25 mile battlefield of pot holes. With that said, a rental is highly recommended if you don't want to put your vehicle through that kinda stress.
Kelso Dunes are quite a marvel, but I wouldn't recommend visiting if you are not an avid hiker or fond of the stair master because the never ending sinking incline is no joke.
Takeway: Once you've hiked a dune, you've hiked them all.