The calculated distance (air line) between As Saffānīyah and Al Qaţīf is approximately 125 miles respectively 201 kilometers.
By car or train, the actual journey to Al Qaţīf is certainly longer, as only the direct route (as the crow flies) between As Saffānīyah and Al Qaţīf has been calculated here.
Air line (approximately)
201 kilometers
108 nautical miles