The calculated distance (air line) between Veľký Krtíš and Trenčín is approximately 76 miles respectively 123 kilometers.
By car or train, the actual journey to Trenčín is certainly longer, as only the direct route (as the crow flies) between Veľký Krtíš and Trenčín has been calculated here.
Air line (approximately)
123 kilometers
66 nautical miles