The calculated distance (air line) between Bolligen and Zürich (Kreis 9) is approximately 54 miles respectively 87 kilometers.
By car or train, the actual journey to Zürich (Kreis 9) is certainly longer, as only the direct route (as the crow flies) between Bolligen and Zürich (Kreis 9) has been calculated here.
Air line (approximately)
87 kilometers
47 nautical miles