The calculated distance (air line) between Néa Moudhaniá and Kallithéa is approximately 160 miles respectively 258 kilometers.
By car or train, the actual journey to Kallithéa is certainly longer, as only the direct route (as the crow flies) between Néa Moudhaniá and Kallithéa has been calculated here.
Air line (approximately)
258 kilometers
139 nautical miles