Complex sentence: Concert orchestras operate in Bismarck, Fargo, Grand Forks, and Minot; of these, the Fargo-Moorhead Symphony Orchestra is the largest, while the Greater Grand Forks Symphony is the oldest.
Split into simpler sentences: Concert orchestras operate in Bismarck, Fargo, Grand Forks, and Minot. Of these, the Fargo-Moorhead Symphony Orchestra is the largest, while the Greater Grand Forks Symphony is the oldest.