The calculated distance (air line) between Rheinfelden and Zürich (Kreis 11) is approximately 35 miles respectively 57 kilometers.
By car or train, the actual journey to Zürich (Kreis 11) is certainly longer, as only the direct route (as the crow flies) between Rheinfelden and Zürich (Kreis 11) has been calculated here.
Air line (approximately)
57 kilometers
31 nautical miles