The calculated distance (air line) between Ágios Stéfanos and Petroúpolis is approximately 12 miles respectively 19 kilometers.
By car or train, the actual journey to Petroúpolis is certainly longer, as only the direct route (as the crow flies) between Ágios Stéfanos and Petroúpolis has been calculated here.
Air line (approximately)
19 kilometers
10 nautical miles