The calculated distance (air line) between Sen Monorom and Kampong Chhnang is approximately 171 miles respectively 275 kilometers.
By car or train, the actual journey to Kampong Chhnang is certainly longer, as only the direct route (as the crow flies) between Sen Monorom and Kampong Chhnang has been calculated here.
Air line (approximately)
275 kilometers
148 nautical miles