The calculated distance (air line) between Slawharad and Svyetlahorsk is approximately 77 miles respectively 123 kilometers.
By car or train, the actual journey to Svyetlahorsk is certainly longer, as only the direct route (as the crow flies) between Slawharad and Svyetlahorsk has been calculated here.
Air line (approximately)
123 kilometers
67 nautical miles