73 km north of Amman, and a short journey northwest from Jerash, through a beautiful pine-forest and olive groves, brings you to the town of Ajloun, where Hadrian stayed over the winter of 129-30 AD, and built himself an arch well outside the town, leaving unbonded its sides for future city walls to come out to meet it.

Here you will find the Castle of Ajloun or Qalaat Errabadh (Arabic for "Hilltop Castle"), from which there is a splendid view westwards into the Jordan Valley. It looks like a Crusader fortress, but it was built by Muslims in 1184-85 as a military fort and buffer to protect the region from invading Crusader forces. It was built on the orders of the local governor, Ezz Eddin Osama bin Munqethe, a nephew of the Ayyubid leader Salahuddin Al-Ayyoubi (Saladin), as a direct retort to the new Latin castle of Belvoir (Kawkab El-Hawa) on the opposite side of the valley between the Tiberias and Besan, and as a base to develop and control the iron mines of Ajloun