This has to be the strangest natural phenomenon I have ever encountered. In The Racetrack in Death Valley are rocks that move. I don't believe anyone has yet ever seen them in the act of moving, but the rocks have left evidence of their movement in the dried mudflat.

Long sinuous trails stream to the east from small rocks that litter the southeast end of the playa.

The picture on the left has a cow rib bone for scale. I have no idea why I brought a cow rib bone all the way out there.

A red arrow points to the rock that made the trail in the picture on the right. It was 39 paces between that rock and the rock hammer in the foreground. For scale, the same cow rib bone is to the left of the rock. As you can see, these rocks sure get around!

The theory of why this happens is that in winter the mudflat is wet and muddy, and a layer of ice freezes on top of it. Strong winds then somehow blow the ice sheet to the west, dragging the rocks along with it, and the rocks scrape the trail in the mud. This all soon dries out, leaving what you see in the pictures.

© 1995  hippotaur