Ajloun Castle, also known as, is a 12th-century Muslim castle situated in northwestern Jordan. It is placed on a hilltop belonging to the Jabal Ajlun district, also known as Jabal ‘Auf after a Bedouin tribe which had captured the area in the 12th century. From its high ground the castle was guarding three wadis which descend towards the Jordan Valley. It was built by the Ayyubids in the 12th century and enlarged by the Mamluks in the 13th.

The name ‘Ajlun goes back to a Christian monk who lived on this mountain in the Byzantine Period. The castle stands on the ruins of a monastery, traces of which were discovered during archaeological excavations.

The castle has been the nucleus of a settlement which has grown to become the present town of Ajloun. The castle’s developing faubourg led to its second name, Qal’at ar-Rabad, “the castle of the faubourg” or “the castle with the suburbs”. This name still resonates in the surname of a large and reputable Christian family owning most of the agricultural lands in the direct vicinity of the castle until this day, the Al-Rabadis.