The calculated distance (air line) between Rosignano Solvay-Castiglioncello and Modena is approximately 90 miles respectively 145 kilometers.
By car or train, the actual journey to Modena is certainly longer, as only the direct route (as the crow flies) between Rosignano Solvay-Castiglioncello and Modena has been calculated here.
Air line (approximately)
145 kilometers
78 nautical miles