The Sliding Rocks of Racetrack Playa

One of the most interesting mysteries of Death Valley National Park is the sliding rocks at Racetrack Playa (a playa is a dry lake bed). These rocks can be found on the floor of the playa with long trails behind them. Somehow these rocks slide across the playa, cutting a furrow in the sediment as they move.

No one knows for sure exactly how these rocks move - although a few people have come up with some pretty good explanations. The reason why their movement remains a mystery: No one has ever seen them in motion!

The prevailing winds that blow across Racetrack Playa travel from southwest to northeast. Most of the rock trails are parallel to this direction. This is strong evidence that wind is the prime mover or at least involved with the motion of the rocks.