The calculated distance (air line) between Ma'rib and Al Ḩudaydah is approximately 165 miles respectively 265 kilometers.
By car or train, the actual journey to Al Ḩudaydah is certainly longer, as only the direct route (as the crow flies) between Ma'rib and Al Ḩudaydah has been calculated here.
Air line (approximately)
265 kilometers
143 nautical miles