The calculated distance (air line) between Yuen Long Kau Hui and Sanshui is approximately 88 miles respectively 141 kilometers.
By car or train, the actual journey to Sanshui is certainly longer, as only the direct route (as the crow flies) between Yuen Long Kau Hui and Sanshui has been calculated here.
Air line (approximately)
141 kilometers
76 nautical miles