The calculated distance (air line) between Dresden and Rychnov nad Kněžnou is approximately 127 miles respectively 204 kilometers.
By car or train, the actual journey to Rychnov nad Kněžnou is certainly longer, as only the direct route (as the crow flies) between Dresden and Rychnov nad Kněžnou has been calculated here.
Air line (approximately)
204 kilometers
110 nautical miles