The calculated distance (air line) between Sant Boi de Llobregat and Viladecans is approximately 2 miles respectively 4 kilometers.
By car or train, the actual journey to Viladecans is certainly longer, as only the direct route (as the crow flies) between Sant Boi de Llobregat and Viladecans has been calculated here.
Air line (approximately)
4 kilometers
2 nautical miles