The calculated distance (air line) between Ḩalfāyā and Khān Shaykhūn is approximately 13 miles respectively 21 kilometers.
By car or train, the actual journey to Khān Shaykhūn is certainly longer, as only the direct route (as the crow flies) between Ḩalfāyā and Khān Shaykhūn has been calculated here.
Air line (approximately)
21 kilometers
11 nautical miles