The calculated distance (air line) between Kumburgaz and Büyükçekmece is approximately 5 miles respectively 9 kilometers.
By car or train, the actual journey to Büyükçekmece is certainly longer, as only the direct route (as the crow flies) between Kumburgaz and Büyükçekmece has been calculated here.
Air line (approximately)
9 kilometers
5 nautical miles