The calculated distance (air line) between Fuente-Álamo de Murcia and Cartagena is approximately 13 miles respectively 21 kilometers.
By car or train, the actual journey to Cartagena is certainly longer, as only the direct route (as the crow flies) between Fuente-Álamo de Murcia and Cartagena has been calculated here.
Air line (approximately)
21 kilometers
11 nautical miles