Mars is the fourth planet from the Sun and the seventh largest in the Solar System. A cold, dusty desert world with a thin atmosphere (mostly CO₂), the planet features extinct volcanoes, deep canyons, polar ice caps, and seasons. Mars has two small moons (Phobos and Deimos), a day just over 24 hours long, and a year lasting about 687 Earth days. It is a prime focus of robotic exploration and studies about past water and habitability.
Source: science.nasa.gov
05/06/2006

Here is a road never traveled. To get to Victoria Crater on Mars, the rolling robotic rover Opportunity must traverse the landscape shown above. Victoria Crater lies about one kilometer ahead. The intervening terrain shows a series of light rock outcrops that appears like some sort of cobblestone road. Surrounding this naturally-occurring Martian road, is Martian sand ripples that must be navigated around. Inspection of the outcrop road shows it to be sprinkled with many small round rocks dubbed blueberries. Opportunity and its sister robot Spirit continue their third year exploring Mars. Within the next month, planetary scientists hope to maneuver Opportunity across Meridiani Planum to get a good view of 800-meter diameter Victoria Crater.