Dibeen Forest Reserve extends over 8.5 km2 of mountainous terrain, covering an area of pristine pine-oak habitat (Pinus halipensis-Quercus calliprinos). These Aleppo pines are some of the oldest and largest in the Kingdom, and are the defining characteristic of this landscape, representing the southeastern geographical limit of this forest type. Dibeen is the driest part of the world in which the Aleppo pines are known to grow naturally, with an average rainfall of around 400mm per year.