Rover Tracks

Tracks made by the Sojourner rover are visible in this image, taken by one of the cameras aboard Sojourner on Sol 3. The tracks represent the rover maneuvering towards the rock dubbed "Barnacle Bill." The rover, having exited the lander via the rear ramp, first traveled towards the right portion of the image, and then moved forward towards the left where Barnacle Bill sits. The fact that the rover was making defined tracks indicates that the soil is made up of particles on a micron scale.

http://photojournal.jpl.nasa.gov/catalog/PIA00633