The calculated distance (air line) between L'Haÿ-les-Roses and Boulogne-Billancourt is approximately 6 miles respectively 9 kilometers.
By car or train, the actual journey to Boulogne-Billancourt is certainly longer, as only the direct route (as the crow flies) between L'Haÿ-les-Roses and Boulogne-Billancourt has been calculated here.
Air line (approximately)
9 kilometers
5 nautical miles