I've been reading this with interest (having an obsessive BC), but, my heart says, poor soul!

As had been said, this dog needs to be doing something. I do hope she gets the chance to fulfil her potential.

Collies, particularly understimulated collies, can be prone to obsessive behaviour patterns, but, and it is a big but, this type of obsessive circling can also be a symptom of epileptic seizure activity - hence my question of whether she can be distracted from the circling. If not, vet check and very likely anti-convulsant medication. If she can be distracted, then more variety in her daily activities and distracting every time the behaviour starts to break the habit.

My rescue Malinois girl does this, too.

Always clockwise, and whenever she is stressed, excited, bored, happy.... well, she doesn't really need an excuse! She can be snapped out of it, but her age is indeterminate (10-ish we think maybe more?) and it seems that she has certainly been kept kennelled in the past, and also at some point lived indoors but been put in an outdoor kennel at night.

At her age it's something I can probably minimise but doubt I can really stop.

Kennellosis is hard to break, you see the same thing in zoo animals, but the pastoral breeds do tend to be more prone to this condition; their hard wired shepherding instincts being denied.

Sounds like the dog could be needing a lot more distraction/exercise in its life! I know with my BC, unless she gets around 8 miles at least per day, she would go stir crazy and us with her !!