The calculated distance (air line) between Martorell and Sant Boi de Llobregat is approximately 11 miles respectively 17 kilometers.
By car or train, the actual journey to Sant Boi de Llobregat is certainly longer, as only the direct route (as the crow flies) between Martorell and Sant Boi de Llobregat has been calculated here.
Air line (approximately)
17 kilometers
9 nautical miles