The calculated distance (air line) between Zemer and Rosh Ha‘Ayin is approximately 19 miles respectively 31 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 Zemer and Rosh Ha‘Ayin has been calculated here.
Air line (approximately)
31 kilometers
17 nautical miles