The calculated distance (air line) between So Uk and Tuen Mun San Hui is approximately 12 miles respectively 20 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 So Uk and Tuen Mun San Hui has been calculated here.
Air line (approximately)
20 kilometers
11 nautical miles