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