Rabe Crater, Mars

Rabe Crater is a 108 km-wide impact crater with an intricately shaped dune field. The dune material likely comprises locally eroded sediments that have been shaped by prevailing winds. Other smaller craters in the region also contain these dark deposits. One relatively young and deep crater can be seen in the upper left; as well as the dark material, channels and grooves are clearly visible in its crater walls.

via European Space Agency