The calculated distance (air line) between Kowloon Tong and Kam Ying is approximately 7 miles respectively 12 kilometers.
By car or train, the actual journey to Kam Ying is certainly longer, as only the direct route (as the crow flies) between Kowloon Tong and Kam Ying has been calculated here.
Air line (approximately)
12 kilometers
6 nautical miles