The calculated distance (air line) between Duchcov and Ústí nad Labem is approximately 13 miles respectively 21 kilometers.
By car or train, the actual journey to Ústí nad Labem is certainly longer, as only the direct route (as the crow flies) between Duchcov and Ústí nad Labem has been calculated here.
Air line (approximately)
21 kilometers
11 nautical miles