The northernmost mountains of the Hajar range are found on the Musandam Peninsula. For this reason, the phrase Ru'us al-Jibal (Heads of the Mountains) is applied to them, or the peninsula itself. Despite being physically part of the western Hajar, they differ in geology and hydrology to the rest of the range. The highest point in the UAE is located at Jebel Jais near Ras Al Khaimah, which measures from sea level, but since the summit is on the Omani side, Jabal Yibir, measuring over , has the highest peak in the UAE.