The calculated distance (air line) between Altopascio and Montelupo Fiorentino is approximately 18 miles respectively 28 kilometers.
By car or train, the actual journey to Montelupo Fiorentino is certainly longer, as only the direct route (as the crow flies) between Altopascio and Montelupo Fiorentino has been calculated here.
Air line (approximately)
28 kilometers
15 nautical miles