For the rocks I used the horizontal part of the racks. Free transform and liquify. Also used the craquelere filter and dodge and burn.
step 8 of 12
Making of the rocks:
Using the horizontal wooden bar in front of the train we liquify it with a big brush (240px) to give it some shape.
Then using a smaller brush in the liquify tool (7px) we make small strokes to create little peaks as the red arrows show.
step 9 of 12
Use the dodge tool at 10% strength to highlight parts of the rock.
step 10 of 12
With the burn tool at 13% we give more shape to the rocks.
step 11 of 12
We select the craquelure filter.
step 12 of 12
For this filter we set the crack spacing to 15, crack depth to 6, and crack brightness to 9.
If needed we use the liquify tool to reshape the little peaks.
Then we use the finished shape in multiple layers to create the rocks and give it some depth using separate layers where we paint the fog.