The calculated distance (air line) between Modi‘in Makkabbim Re‘ut and Rosh Ha‘Ayin is approximately 14 miles respectively 23 kilometers.
By car or train, the actual journey to Rosh Ha‘Ayin is certainly longer, as only the direct route (as the crow flies) between Modi‘in Makkabbim Re‘ut and Rosh Ha‘Ayin has been calculated here.
Air line (approximately)
23 kilometers
12 nautical miles