The Surface of Mars by The Curiosity Rover
We have had multiple rovers on Mars which have been taking pictures
This is a 360 degree picture of a small piece of the Bagnold Dunes. This picture is made up of 115 different images taken on March 24 and March 25 of this year. This picture is “white-balanced” so that the surface looks like like how it would under full sunlight on Earth. This makes comparison between the two easier. [1]
Sand Dunes take far longer to form on Mars. This is because of the atmosphere. The atmosphere on Mars is about 1/100th the density of Earth's. However, this does not mean it cannot support clouds, weather, and wind. In fact the dust storms on Mars are the largest in the solar system (although not the thickest). This is most likely because the dust particles absorb sunlight, heating up the particles near them and increasing its size. [2]
awesome pics snapped on an awesome day - 24 march(my birthday) :p