The calculated distance (air line) between Seini and Piatra Neamţ is approximately 154 miles respectively 248 kilometers.
By car or train, the actual journey to Piatra Neamţ is certainly longer, as only the direct route (as the crow flies) between Seini and Piatra Neamţ has been calculated here.
Air line (approximately)
248 kilometers
134 nautical miles