The outer walls are approximately four metres thick at the base and the interior of the tower is enclosed by a barrel vaulted roof.

[1] The tower is situated in a commanding position on the crest of Marfa Ridge at the north-west end of Malta, overlooking the natural harbour and the potential enemy landing site of Mellieħa Bay, with clear views over to Comino and Gozo, and also eastward to the line of watchtowers along the north shore of Malta that linked it with the Knights headquarters in Valletta.

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 tower was gradually restored by Din l-Art Ħelwa, starting in 1999 and completed in 2001, assisted by substantial industrial sponsorship.

Due to the extreme unevenness of the floor, this was recently covered by a wooden surface with glass apertures through which one can view the original slabs.