The calculated distance (air line) between Mělník and Frýdek-Místek is approximately 178 miles respectively 287 kilometers.
By car or train, the actual journey to Frýdek-Místek is certainly longer, as only the direct route (as the crow flies) between Mělník and Frýdek-Místek has been calculated here.
Air line (approximately)
287 kilometers
155 nautical miles