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