The calculated distance (air line) between Ariel and Rishon LeTsiyyon is approximately 25 miles respectively 40 kilometers.
By car or train, the actual journey to Rishon LeTsiyyon is certainly longer, as only the direct route (as the crow flies) between Ariel and Rishon LeTsiyyon has been calculated here.
Air line (approximately)
40 kilometers
22 nautical miles