The calculated distance (air line) between Petit-Bourg and Pointe-Noire is approximately 13 miles respectively 22 kilometers.
By car or train, the actual journey to Pointe-Noire is certainly longer, as only the direct route (as the crow flies) between Petit-Bourg and Pointe-Noire has been calculated here.
Air line (approximately)
22 kilometers
12 nautical miles