The calculated distance (air line) between Tai Kok Tsui and Ma On Shan is approximately 8 miles respectively 12 kilometers.
By car or train, the actual journey to Ma On Shan is certainly longer, as only the direct route (as the crow flies) between Tai Kok Tsui and Ma On Shan has been calculated here.
Air line (approximately)
12 kilometers
7 nautical miles