The calculated distance (air line) between Veľký Krtíš and Staré Mesto is approximately 104 miles respectively 168 kilometers.
By car or train, the actual journey to Staré Mesto is certainly longer, as only the direct route (as the crow flies) between Veľký Krtíš and Staré Mesto has been calculated here.
Air line (approximately)
168 kilometers
91 nautical miles