The calculated distance (air line) between Poznań and Tarnowskie Góry is approximately 159 miles respectively 256 kilometers.
By car or train, the actual journey to Tarnowskie Góry is certainly longer, as only the direct route (as the crow flies) between Poznań and Tarnowskie Góry has been calculated here.
Air line (approximately)
256 kilometers
138 nautical miles