The calculated distance (air line) between Sv. Trojica v Slov. Goricah and Ptuj is approximately 11 miles respectively 17 kilometers.
By car or train, the actual journey to Ptuj is certainly longer, as only the direct route (as the crow flies) between Sv. Trojica v Slov. Goricah and Ptuj has been calculated here.
Air line (approximately)
17 kilometers
9 nautical miles