The calculated distance (air line) between Duchcov and Jablonec nad Nisou is approximately 63 miles respectively 101 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 Duchcov and Jablonec nad Nisou has been calculated here.
Air line (approximately)
101 kilometers
55 nautical miles