The calculated distance (air line) between Abū Ghurayb and Al Fallūjah is approximately 23 miles respectively 37 kilometers.
By car or train, the actual journey to Al Fallūjah is certainly longer, as only the direct route (as the crow flies) between Abū Ghurayb and Al Fallūjah has been calculated here.
Air line (approximately)
37 kilometers
20 nautical miles