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