The calculated distance (air line) between Bischofsheim in der Rhön and Dortmund is approximately 135 miles respectively 217 kilometers.
By car or train, the actual journey to Dortmund is certainly longer, as only the direct route (as the crow flies) between Bischofsheim in der Rhön and Dortmund has been calculated here.
Air line (approximately)
217 kilometers
117 nautical miles