The calculated distance (air line) between Ostrava and Jablonec nad Nisou is approximately 150 miles respectively 242 kilometers.
By car or train, the actual journey to Jablonec nad Nisou is certainly longer, as only the direct route (as the crow flies) between Ostrava and Jablonec nad Nisou has been calculated here.
Air line (approximately)
242 kilometers
131 nautical miles