The exact date of the fort 's construction is unknown .
It was likely erected after 1153 following Amalric 's capture of Ascalon to the north from the Fatimid Caliphate .
The exact date of the fort 's construction is unknown , although it was likely erected after 1153 following Amalric 's capture of Ascalon to the north from the Fatimid Caliphate .