Opportunity's road to Victoria crater. A sol is a Martian day, 25.5 Earth hours. Opportunity is currently at around 1680 sols and hanging around the south end of Victoria for a while before setting off for crater Endevour.
Here is a remarkable false color photo of Victoria from the Mars Reconnaissance Orbiter in early 2007. Click on the image for a large version where you can see the rover. The crater is 800m across.
This is a ground view of the crater in natural color. The rover is looking north towards its position in the shot above.