The most outstanding attraction of the Maltese island of Comino can be seen from Malta, Gozo, as well as any part of the ferry passing between the islands. Once in the early 17th century, St. Mary's Tower played an important role as the island's defender against the Barbary corsairs, who were engaged in looting in the coastal waters of the Mediterranean Sea. The magnificent defensive monument, the author of which is still unknown, was recognized as the most expensive fortification project of that time. But even today, its solid walls make a strong impression on travelers.

The building of a regular square shape with four corner towers rises almost 80 meters above sea level. The height of the tower itself is 12 meters, and the thickness of its stone walls reaches almost 6 meters. A solid foundation of the tower occupies another 8 meters. Previously, it housed a shooting gallery. Unfortunately, it has not survived to this day, unlike the deep moat surrounding the ancient tower. Inside, there was a chapel dedicated to St. Joseph, which can still be seen today.

In the 18th century, the entire island of Comino was a place of exile for convicted knights, and the tower served as a prison, But in the early 19th century, it was abandoned. Later, its solid walls were used during the First and Second World Wars, and in 1925, the tower was included in the Antiquities List of Malta.

The majestic St. Mary's Tower was the fifth of six legendary towers, built by the Grand Master Alof de Vignacur order. Until 2002, it was used by the Armed Forces of Malta as protection against smugglers and illegal hunting of migratory birds. Today, most of the tower's premises are open to tourists, including an observation deck that offers a marvelous view of the famous Blue Lagoon and the picturesque shores of the neighboring island of Gozo.