The calculated distance (air line) between Monte Porzio Catone and Grottaferrata is approximately 3 miles respectively 5 kilometers.
By car or train, the actual journey to Grottaferrata is certainly longer, as only the direct route (as the crow flies) between Monte Porzio Catone and Grottaferrata has been calculated here.
Air line (approximately)
5 kilometers
3 nautical miles