The story as I heard it:

Two Jacobite soldiers were imprisoned at Carlisle (a castle in the English/Scottish Borders) toward the end of the -- I think -- 1745 rebellion. The next morning, one of the soldiers was to be freed, the other hanged. The condemned man sings of his sweetheart, whom'll he'll never see again, tells the soldier who is to be freed: "You'll take the high road (of the living), and I'll take the low road (of the dead)..." The low road is faster.

The Corries do a slow, lyric version of the song which combines the traditional "Loch Lomond" with the verses sung from the sweetheart's point of view (in the database as "Loch Lomond II"). It's absolutely heart-wrenching.

Tamara
tamarad@dolphin.upenn.edu