The calculated distance (air line) between Lucca and Montecatini-Terme is approximately 14 miles respectively 22 kilometers.
By car or train, the actual journey to Montecatini-Terme is certainly longer, as only the direct route (as the crow flies) between Lucca and Montecatini-Terme has been calculated here.
Air line (approximately)
22 kilometers
12 nautical miles