The calculated distance (air line) between Utsunomiya and Ōtawara is approximately 22 miles respectively 36 kilometers.
By car or train, the actual journey to Ōtawara is certainly longer, as only the direct route (as the crow flies) between Utsunomiya and Ōtawara has been calculated here.
Air line (approximately)
36 kilometers
19 nautical miles