The calculated distance (air line) between Ma On Shan and Tuen Mun San Hui is approximately 17 miles respectively 27 kilometers.
By car or train, the actual journey to Tuen Mun San Hui is certainly longer, as only the direct route (as the crow flies) between Ma On Shan and Tuen Mun San Hui has been calculated here.
Air line (approximately)
27 kilometers
15 nautical miles