The calculated distance (air line) between Cill Airne and Droichead Nua is approximately 138 miles respectively 222 kilometers.
By car or train, the actual journey to Droichead Nua is certainly longer, as only the direct route (as the crow flies) between Cill Airne and Droichead Nua has been calculated here.
Air line (approximately)
222 kilometers
120 nautical miles