The calculated distance (air line) between Sarzana and Santo Stefano di Magra is approximately 3 miles respectively 5 kilometers.
By car or train, the actual journey to Santo Stefano di Magra is certainly longer, as only the direct route (as the crow flies) between Sarzana and Santo Stefano di Magra has been calculated here.
Air line (approximately)
5 kilometers
3 nautical miles