Nahr al-Allan

[1][2] The Allan is one of the tributaries of the Yarmuk, which marks part of the national border of Syria and Jordan.

[3] The river flows southward from the foot of the Tell al-Hara mound (the highest point in the Hauran plain) through the stony, volcanic cone-covered country where the river has an altitude of approximately 440 meters (1,440 ft) above sea level.

Here it is slightly lower than the roughly parallel Ruqqad river 5.5 kilometers (3.4 mi) to the Allan's west.

The river becomes narrow at this point and is joined by a ravine called the Wadi Beit Akkar.

[6] Around 2 miles (3.2 km) after the Allan passes Hayt it is joined by Nahr al-Harir (or Ehreir) and after a further 2 miles (3.2 km) the joint river terminates at the Yarmuk at an elevation of 55 meters (180 ft) above sea level.