The calculated distance (air line) between Šmartno ob Paki and Mengeš is approximately 25 miles respectively 40 kilometers.
By car or train, the actual journey to Mengeš is certainly longer, as only the direct route (as the crow flies) between Šmartno ob Paki and Mengeš has been calculated here.
Air line (approximately)
40 kilometers
21 nautical miles