The calculated distance (air line) between San Marcos and Naucalpan de Juárez is approximately 186 miles respectively 299 kilometers.
By car or train, the actual journey to Naucalpan de Juárez is certainly longer, as only the direct route (as the crow flies) between San Marcos and Naucalpan de Juárez has been calculated here.
Air line (approximately)
299 kilometers
161 nautical miles