The calculated distance (air line) between Český Brod and Mladá Boleslav is approximately 23 miles respectively 38 kilometers.
By car or train, the actual journey to Mladá Boleslav is certainly longer, as only the direct route (as the crow flies) between Český Brod and Mladá Boleslav has been calculated here.
Air line (approximately)
38 kilometers
20 nautical miles