In the 15th century, Marina was under increasing threat from an Ottoman invasion, so a castle was built to defend the inhabitants. In 1495, the Venetian government gave its consent to the then Bishop of Trogir, Frano Marcello (Francesco Marcello), to build a fortress in the bay of Bosiljine (Saldun), near the church of Sv. Marina (St Marina). In the same project, external defensive walls were built together with the Tower and the Citadel, which are a unique example of medieval residential and fortification architecture. The village could be entered by the main Western Gate (Vela vrata) secured by corner towers, from which, adapting to the terrain to the south and southeast, a defensive wall ran in a semicircle, consisting of family houses, all the way to the seashore in the north. If you walk along street Put bedema today, descending to the north along the wall, you will arrive to the East Gate (Mala vrata), the second and smaller entrance to the village. The top floors of houses made of massive carved stone could be quickly converted into defensive positions, should the need arise. The rest of the medieval housing-fortification terminology has remained in the internal division of the village until today. The outer defensive walls and residential buildings of Marina were severely damaged in the Ottoman siege of 1657, the remains of which are still visible today - while some houses were rebuilt immediately after these events and are inhabited by descendants of old families of Marina.