The calculated distance (air line) between Šmartno pri Litiji and Maribor is approximately 52 miles respectively 84 kilometers.
By car or train, the actual journey to Maribor is certainly longer, as only the direct route (as the crow flies) between Šmartno pri Litiji and Maribor has been calculated here.
Air line (approximately)
84 kilometers
45 nautical miles