The calculated distance (air line) between Néa Smýrni and Néa Ionía is approximately 7 miles respectively 11 kilometers.
By car or train, the actual journey to Néa Ionía is certainly longer, as only the direct route (as the crow flies) between Néa Smýrni and Néa Ionía has been calculated here.
Air line (approximately)
11 kilometers
6 nautical miles