The calculated distance (air line) between Omurtag and Veliko Tŭrnovo is approximately 40 miles respectively 64 kilometers.
By car or train, the actual journey to Veliko Tŭrnovo is certainly longer, as only the direct route (as the crow flies) between Omurtag and Veliko Tŭrnovo has been calculated here.
Air line (approximately)
64 kilometers
35 nautical miles