The calculated distance (air line) between San Donnino and Reggio nell'Emilia is approximately 67 miles respectively 108 kilometers.
By car or train, the actual journey to Reggio nell'Emilia is certainly longer, as only the direct route (as the crow flies) between San Donnino and Reggio nell'Emilia has been calculated here.
Air line (approximately)
108 kilometers
59 nautical miles