The calculated distance (air line) between Néa Kallikráteia and Chalkída is approximately 131 miles respectively 211 kilometers.
By car or train, the actual journey to Chalkída is certainly longer, as only the direct route (as the crow flies) between Néa Kallikráteia and Chalkída has been calculated here.
Air line (approximately)
211 kilometers
114 nautical miles