These were defensive towers built detached from a main defensive wall line. They were connected to the rest of a fortification via a bridge or an arcade. Albarrana Towers were developed by Muslim fortification builders between the 8th to 15th Centuries. They are a particular feature in many Moorish castles and defensive structure found in 12th Century Spain. The Tower was basically squared and built several hundred feet from the main perimeter wall. When said bridge was built to the Albarrana, it was made of wood with a removable section. When besieged, this section could easily be removed, thus isolating the Tower. If the Tower fell to an enemy, they would be unable to use it to access the castle or fortification.