The calculated distance (air line) between Jardine's Lookout and Sheung Shui is approximately 18 miles respectively 29 kilometers.
By car or train, the actual journey to Sheung Shui is certainly longer, as only the direct route (as the crow flies) between Jardine's Lookout and Sheung Shui has been calculated here.
Air line (approximately)
29 kilometers
15 nautical miles