On Tophal islet, by the southwest coast of Skadar Lake, opposite Ostros, there are remains of a powerful tower, by its conception very similar to pirgs (medieval towers) on the Holy Mountain .
The tower was probably built in the 14th century, in the period when other monasteries on the islands of Skadar Lake were constructed.
The tower used to control the access from the east i.e. from Skadar to the islands, which were inhabited in the Middle Ages. Most likely, the tower was a part of a defensive system of islands with monasteries on them – Moracnik, Beška and Starceva Gorica, and it controlled water access to the coast leading to the Virgin of Krajina.
Of all preserved medieval fortifications in Montenegro , the tower on Tophala is of simplest form and function. The tower is square in plan, with four strong pilasters at the corners and additional four in the walls between them. The entrance was on the first floor. It was built of bigger pieces of crushed and rough-hewn stones, in mortar. The walls are 2 m thick. The lower part of the tower is well preserved today. Near the tower, remains of foundations of a trefoil church have been discovered. The church is supposed to have been built in the 12th century and to have served as a model to other trefoil/triconch churches built on Skadar Lake islands during the 14th century.