With an average elevation of 1,301 metres (4,268 ft) above sea level, the sixth highest point in Djibouti, they are situated near the border with Ethiopia.

The mountains constitute the highest point in Ali Sabieh region.

Arrei Mountain's altitude and location and topography frequently lead to cool and cloudy weather conditions, which can pose a danger to ill-equipped walkers.

The Arrei Mountains receives the bulk of its precipitation between the months of June and mid-September, averaging just under 269 mm of rainfall annually.

Arrei Mountains receives additional precipitation in the form of fog and summer rains.