This is a defence tower from the Islamic era, 10th to 12th century. Built at a strategic location, at the highest point of the hill, it had a great view of the Minorca channel. It has a square base and its original height, about 10 metres, would have been approximately double that of nowadays. It was built following the adobe technique, with walls made with kneaded earth, pressed with wooden formwork and dried in the fresh air.
It still has some of its embrasures (small slit Windows). It is the original structure from which the fortress evolved.
In 1231 the Treaty of Capdepera was signed with the Minorca Muslims.
In the 19th century a flour mill was built in its interior, with a round tower and spiral staircase, features that can still be seen today.