The calculated distance (air line) between Altendorf and Zürich (Kreis 3) is approximately 20 miles respectively 31 kilometers.
By car or train, the actual journey to Zürich (Kreis 3) is certainly longer, as only the direct route (as the crow flies) between Altendorf and Zürich (Kreis 3) has been calculated here.
Air line (approximately)
31 kilometers
17 nautical miles