Montreal is a Crusader castle on the eastern side of the Arabah, perched on the side of a rocky, conical mountain, looking out over fruit trees below. The ruins, called Shoubak, are located in modern town of Shoubak in Jordan.
The castle was built in 1115 by Baldwin I of Jerusalem during his expedition to the area where he captured Aqaba on the Red Sea in 1116. Originally called 'Krak de Montreal' or 'Mons Regalis', it was named in honor of the king's own contribution to its construction (Mont Royal).
Little remains of the original Crusader fortifications. Although it has never been fully excavated, it is known that there was a set of three walls, which partially remain. The most significant remains of the crusader portions of the crusader castle is the remains of a curtain wall that ran inside the later Muslim additions and two chapels.