The calculated distance (air line) between Méry-sur-Oise and L'Isle-Adam is approximately 4 miles respectively 6 kilometers.
By car or train, the actual journey to L'Isle-Adam is certainly longer, as only the direct route (as the crow flies) between Méry-sur-Oise and L'Isle-Adam has been calculated here.
Air line (approximately)
6 kilometers
3 nautical miles