The calculated distance (air line) between Saint-Mihiel and Marne La Vallée is approximately 132 miles respectively 213 kilometers.
By car or train, the actual journey to Marne La Vallée is certainly longer, as only the direct route (as the crow flies) between Saint-Mihiel and Marne La Vallée has been calculated here.
Air line (approximately)
213 kilometers
115 nautical miles