The calculated distance (air line) between Yuen Long Kau Hui and Luoyang is approximately 52 miles respectively 83 kilometers.
By car or train, the actual journey to Luoyang is certainly longer, as only the direct route (as the crow flies) between Yuen Long Kau Hui and Luoyang has been calculated here.
Air line (approximately)
83 kilometers
45 nautical miles