The calculated distance (air line) between Kampong Thom and Kampong Speu is approximately 90 miles respectively 145 kilometers.
By car or train, the actual journey to Kampong Speu is certainly longer, as only the direct route (as the crow flies) between Kampong Thom and Kampong Speu has been calculated here.
Air line (approximately)
145 kilometers
78 nautical miles