The calculated distance (air line) between Cologne and Bohain-en-Vermandois is approximately 167 miles respectively 269 kilometers.
By car or train, the actual journey to Bohain-en-Vermandois is certainly longer, as only the direct route (as the crow flies) between Cologne and Bohain-en-Vermandois has been calculated here.
Air line (approximately)
269 kilometers
145 nautical miles