The calculated distance (air line) between Tervel and Veliko Tŭrnovo is approximately 101 miles respectively 162 kilometers.
By car or train, the actual journey to Veliko Tŭrnovo is certainly longer, as only the direct route (as the crow flies) between Tervel and Veliko Tŭrnovo has been calculated here.
Air line (approximately)
162 kilometers
87 nautical miles