The calculated distance (air line) between Morlanwelz-Mariemont and Ostend is approximately 78 miles respectively 125 kilometers.
By car or train, the actual journey to Ostend is certainly longer, as only the direct route (as the crow flies) between Morlanwelz-Mariemont and Ostend has been calculated here.
Air line (approximately)
125 kilometers
68 nautical miles