The calculated distance (air line) between Chartres-de-Bretagne and Cergy-Pontoise is approximately 186 miles respectively 300 kilometers.
By car or train, the actual journey to Cergy-Pontoise is certainly longer, as only the direct route (as the crow flies) between Chartres-de-Bretagne and Cergy-Pontoise has been calculated here.
Air line (approximately)
300 kilometers
162 nautical miles