The calculated distance (air line) between Maxhütte-Haidhof and Mannheim is approximately 164 miles respectively 265 kilometers.
By car or train, the actual journey to Mannheim is certainly longer, as only the direct route (as the crow flies) between Maxhütte-Haidhof and Mannheim has been calculated here.
Air line (approximately)
265 kilometers
143 nautical miles