The calculated distance (air line) between Agios Ioannis Rentis and Kalamariá is approximately 185 miles respectively 297 kilometers.
By car or train, the actual journey to Kalamariá is certainly longer, as only the direct route (as the crow flies) between Agios Ioannis Rentis and Kalamariá has been calculated here.
Air line (approximately)
297 kilometers
161 nautical miles