Robert of Normandy and Robert of Flanders procured timber from the nearby forests. Under the command of Guglielmo Embriaco and Gaston of Béarn, the crusaders began the construction of their siege weapons. They constructed the finest siege equipment of the 11th century in almost 3 weeks. This included: 2 massive wheel-mounted siege towers, a battering ram with an iron-clad head, numerous scaling ladders and a series of portable wattle screens. On the other hand the Fatimids kept an eye on the preparation by the Franks and they set up their mangonels on the wall in the firing range once an assault began. The preparation by the crusaders was complete.