I'm not sure if this is concrete fact, or just a theory, but you can continue the line up Norway's western coast too. Then in the other direction, the line was broken, but restarts & progresses from Nova Scotia down through the Appalachians in North America.
IIRC they were all part of the same Pangaian range, and include Greenland east coast and the Atlas mountains.
I'm gonna be driving along most of Loch Ness early this autumn. Anything in particular I should look out for with respect to the Great Glen Fault? Any less-obvious geologic features?
Not related to the Great Glen Fault but the Parallel Roads in Glen Roy are fairly close and worth a look: