Here is the link to the Wikipedia article mentioning the racetrack.
The name comes from the tracks left on the dry sandy ground which used to be a lake bottom long time ago. The rocks are supposed to move with no human or animal intervention but rather due to slides guiding them to the ground level first from surrounding hills and then sliding over the mud(when it rains) dragged by gusty winds. A typical track lasts 3 to 4 years on average according to Wikipedia. The rocks are called Sailing Stones.