The calculated distance (air line) between Agios Ioannis Rentis and Kifisiá is approximately 11 miles respectively 18 kilometers.
By car or train, the actual journey to Kifisiá is certainly longer, as only the direct route (as the crow flies) between Agios Ioannis Rentis and Kifisiá has been calculated here.
Air line (approximately)
18 kilometers
10 nautical miles