The calculated distance (air line) between Gonbad-e Kāvūs and Esfarāyen is approximately 130 miles respectively 209 kilometers.
By car or train, the actual journey to Esfarāyen is certainly longer, as only the direct route (as the crow flies) between Gonbad-e Kāvūs and Esfarāyen has been calculated here.
Air line (approximately)
209 kilometers
113 nautical miles