The calculated distance (air line) between Montemor-o-Novo and Rio Tinto is approximately 176 miles respectively 283 kilometers.
By car or train, the actual journey to Rio Tinto is certainly longer, as only the direct route (as the crow flies) between Montemor-o-Novo and Rio Tinto has been calculated here.
Air line (approximately)
283 kilometers
153 nautical miles