The calculated distance (air line) between Nowy Dwór Mazowiecki and Gdańsk is approximately 158 miles respectively 254 kilometers.
By car or train, the actual journey to Gdańsk is certainly longer, as only the direct route (as the crow flies) between Nowy Dwór Mazowiecki and Gdańsk has been calculated here.
Air line (approximately)
254 kilometers
137 nautical miles