The calculated distance (air line) between Saint-Lô and Cergy-Pontoise is approximately 143 miles respectively 231 kilometers.
By car or train, the actual journey to Cergy-Pontoise is certainly longer, as only the direct route (as the crow flies) between Saint-Lô and Cergy-Pontoise has been calculated here.
Air line (approximately)
231 kilometers
125 nautical miles