The tower is a massive, rectangular structure featuring five embrasures. The entrance arch was originally equipped with double gates—both a portcullis (a lifting gate) and standard closing doors. The masonry of the tower is Gothic (2–2.6 meters thick), while the ornate attic (the uppermost part of the building) belongs to the Renaissance period.
The Northern Renaissance-style attic was added to the top of the tower likely in the early 17th century, perhaps during the reconstruction of the gates following the fire of 1610. At the center of the facade’s composition is the Vytis (the Lithuanian Coat of Arms), held by two mythological creatures—griffins. In Christian symbolism, this creature, composed of animals that rule over heaven and earth, serves as an image of Christ, the Ruler of the Universe. It is likely no coincidence that they stand above the niche where the icon of the Savior of the World (Salvator Mundi)—Christ—was once displayed. Beneath the cornice of the attic, the head of Hermes (Mercury) can be seen.
Below the attic, in a niche on the second floor, is a fresco of the Savior of the World. This fresco likely replaced the original painting of the same subject, which was executed on wooden panels, during the 18th century. To the right of the Lord is a depiction of St. Casimir; to the left is what appears to be St. Stanislaus, the patron of the Vilnius Cathedral.