Well, the trail already does it, IMO. But I would keep the distant mountain/hilltop kind of bare, perhaps a few patches of trees only. You could (just for experimentation) also try adding a soft (50%) simple shape exactly on that mountain top, masking a surface shader before the compute terrain, where you set smoothing to minus 0-1, and add a crude (size of mountain top, but detail at 0.7-0.95) fractal warp as child. Or a ridged PF displaced up. See what happens. In principle you should get some 'Dolomite' like rocks.
