The calculated distance (air line) between Roztoky and Ústí nad Labem is approximately 38 miles respectively 62 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 Roztoky and Ústí nad Labem has been calculated here.
Air line (approximately)
62 kilometers
33 nautical miles