The calculated distance (air line) between Çatalca and Büyükçekmece is approximately 11 miles respectively 17 kilometers.
By car or train, the actual journey to Büyükçekmece is certainly longer, as only the direct route (as the crow flies) between Çatalca and Büyükçekmece has been calculated here.
Air line (approximately)
17 kilometers
9 nautical miles