The calculated distance (air line) between Vert-Saint-Denis and Cergy-Pontoise is approximately 41 miles respectively 66 kilometers.
By car or train, the actual journey to Cergy-Pontoise is certainly longer, as only the direct route (as the crow flies) between Vert-Saint-Denis and Cergy-Pontoise has been calculated here.
Air line (approximately)
66 kilometers
35 nautical miles