The calculated distance (air line) between Sant Feliu de Llobregat and Sant Andreu is approximately 8 miles respectively 13 kilometers.
By car or train, the actual journey to Sant Andreu is certainly longer, as only the direct route (as the crow flies) between Sant Feliu de Llobregat and Sant Andreu has been calculated here.
Air line (approximately)
13 kilometers
7 nautical miles