This image shows some of the dunefields of Mars.
Click on image for full size
NASA
Martian Dunefields
This is an example of the dunefields of Mars. They are located in the southern hemisphere. They are evidence of planetary resurfacing by wind.
Sand dunes were also seen at equatorial regions by Mars Pathfinder and also by the Viking I lander in the Chryse Planitia Basin (check the large topographic map of Mars for the distances between these two landing sites).
The prevelance of sand dunes is an indication of the importance of wind to the erosion of the Martian landscape.
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