The calculated distance (air line) between Lutsk and Staryi Dobrotvir is approximately 56 miles respectively 90 kilometers.
By car or train, the actual journey to Staryi Dobrotvir is certainly longer, as only the direct route (as the crow flies) between Lutsk and Staryi Dobrotvir has been calculated here.
Air line (approximately)
90 kilometers
49 nautical miles