The calculated distance (air line) between Tai Mei Tuk and Tuen Mun is approximately 18 miles respectively 29 kilometers.
By car or train, the actual journey to Tuen Mun is certainly longer, as only the direct route (as the crow flies) between Tai Mei Tuk and Tuen Mun has been calculated here.
Air line (approximately)
29 kilometers
15 nautical miles