The calculated distance (air line) between Castel San Pietro Terme and San Pietro in Casale is approximately 23 miles respectively 37 kilometers.
By car or train, the actual journey to San Pietro in Casale is certainly longer, as only the direct route (as the crow flies) between Castel San Pietro Terme and San Pietro in Casale has been calculated here.
Air line (approximately)
37 kilometers
20 nautical miles