The calculated distance (air line) between Acilia-Castel Fusano-Ostia Antica and Marino is approximately 17 miles respectively 27 kilometers.
By car or train, the actual journey to Marino is certainly longer, as only the direct route (as the crow flies) between Acilia-Castel Fusano-Ostia Antica and Marino has been calculated here.
Air line (approximately)
27 kilometers
15 nautical miles