The calculated distance (air line) between Gliwice and Tarnowskie Góry is approximately 13 miles respectively 21 kilometers.
By car or train, the actual journey to Tarnowskie Góry is certainly longer, as only the direct route (as the crow flies) between Gliwice and Tarnowskie Góry has been calculated here.
Air line (approximately)
21 kilometers
11 nautical miles