The calculated distance (air line) between Sveti Nikole and Kisela Voda is approximately 24 miles respectively 38 kilometers.
By car or train, the actual journey to Kisela Voda is certainly longer, as only the direct route (as the crow flies) between Sveti Nikole and Kisela Voda has been calculated here.
Air line (approximately)
38 kilometers
21 nautical miles