The calculated distance (air line) between Udine and Šempeter pri Gorici is approximately 22 miles respectively 35 kilometers.
By car or train, the actual journey to Šempeter pri Gorici is certainly longer, as only the direct route (as the crow flies) between Udine and Šempeter pri Gorici has been calculated here.
Air line (approximately)
35 kilometers
19 nautical miles