The calculated distance (air line) between Lütjenburg and Burg auf Fehmarn is approximately 26 miles respectively 43 kilometers.
By car or train, the actual journey to Burg auf Fehmarn is certainly longer, as only the direct route (as the crow flies) between Lütjenburg and Burg auf Fehmarn has been calculated here.
Air line (approximately)
43 kilometers
23 nautical miles