The calculated distance (air line) between Vyalikaya Byerastavitsa and Slonim is approximately 54 miles respectively 88 kilometers.
By car or train, the actual journey to Slonim is certainly longer, as only the direct route (as the crow flies) between Vyalikaya Byerastavitsa and Slonim has been calculated here.
Air line (approximately)
88 kilometers
47 nautical miles