The calculated distance (air line) between Sępólno Krajeńskie and Bielany is approximately 163 miles respectively 262 kilometers.
By car or train, the actual journey to Bielany is certainly longer, as only the direct route (as the crow flies) between Sępólno Krajeńskie and Bielany has been calculated here.
Air line (approximately)
262 kilometers
142 nautical miles