The calculated distance (air line) between Tanushimarumachi-toyoki and Ōkawa is approximately 20 miles respectively 33 kilometers.
By car or train, the actual journey to Ōkawa is certainly longer, as only the direct route (as the crow flies) between Tanushimarumachi-toyoki and Ōkawa has been calculated here.
Air line (approximately)
33 kilometers
18 nautical miles