Scotland was glaciated during the Pleistocene “Ice Ages:”
The signatures of glaciation are manifold in a scene like this. Most prominent and easily recognizable is the broad, relatively flat-bottomed U-shaped valley.
Now check this one out:
That’s a U-turn in a U-shaped valley: the valley is first gouged to the right, then turning around and heading in almost the reverse direction:
Good things these things flow so slow, otherwise that ice may have gotten whiplash.