Andrew Price walks though some parts of how he created a realistic scene with cliff faces in Blender, experimenting with materials, displacements and sculpting with focus on creating the cliff face.

keeping the tutorial explicitly to the theme and will focus just on the cliff face

Andrew notes that the best way to learn is to get going on your own scene, and provides some great examples and inspiration to get you started. Check out Andrew’s post for How to Make a Cliff Face in Blender, where he walks though sculpting and displacements here.