The calculated distance (air line) between Popovo and Veliko Tŭrnovo is approximately 36 miles respectively 57 kilometers.
By car or train, the actual journey to Veliko Tŭrnovo is certainly longer, as only the direct route (as the crow flies) between Popovo and Veliko Tŭrnovo has been calculated here.
Air line (approximately)
57 kilometers
31 nautical miles