The calculated distance (air line) between Slănic and Piatra Neamţ is approximately 117 miles respectively 188 kilometers.
By car or train, the actual journey to Piatra Neamţ is certainly longer, as only the direct route (as the crow flies) between Slănic and Piatra Neamţ has been calculated here.
Air line (approximately)
188 kilometers
101 nautical miles