The calculated distance (air line) between Al Bāb and Dayr Ḩāfir is approximately 18 miles respectively 29 kilometers.
By car or train, the actual journey to Dayr Ḩāfir is certainly longer, as only the direct route (as the crow flies) between Al Bāb and Dayr Ḩāfir has been calculated here.
Air line (approximately)
29 kilometers
16 nautical miles