From Earth Observatory’s caption for this photo:
This simulated natural-color image of southeastern Fars province in southern Iran shows a dry river channel carving through arid mountains toward the northeast. The dry river spreads out across the valley floor in a silvery fan. A broad belt of lush agricultural land follows the curve of the fan and stretches out along a road that runs parallel to the ridgeline. The valley-ward margin of the intensely green agricultural belt fades to dull green along streams (or irrigation canals).
It looks even better at full size.