The calculated distance (air line) between Chlumec nad Cidlinou and Prostějov is approximately 87 miles respectively 141 kilometers.
By car or train, the actual journey to Prostějov is certainly longer, as only the direct route (as the crow flies) between Chlumec nad Cidlinou and Prostějov has been calculated here.
Air line (approximately)
141 kilometers
76 nautical miles