The calculated distance (air line) between Kampong Thom and Svay Rieng is approximately 128 miles respectively 206 kilometers.
By car or train, the actual journey to Svay Rieng is certainly longer, as only the direct route (as the crow flies) between Kampong Thom and Svay Rieng has been calculated here.
Air line (approximately)
206 kilometers
111 nautical miles