 It was the Knights' primary stronghold in the west of Malta, and was manned by a garrison of 30 men, with ammunition and supplies to withstand a siege of 40 days.The ammunition of other fortifications in the north of Malta, such as Aħrax Tower and Wied Musa Battery, was also stored in the tower.Like many of the Knights' early defensive structures, St. Agatha's Tower was strengthened during the early 18th century.