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