Remains of a medieval Tower-House
Research carried out between 1958 and 1976 on the entire island by L. M. Belloni uncovered many buildings used for housing or public use.
There are several visible ruins of buildings carved into the rock along the pathway called “Viale del Poeta”, near the pathway called “Sentiero del bosco”, and in the area where the church of St. Mary was built. Further walls and steps located in other areas of the island point to the existence of earlier buildings.
The best preserved example is the so-called Tower house. The remains of the Tower house stand 3 meters high. The building is almost square in plan (5×5 m). Approximately one third of the southern wall is cut into the rock, while the other three walls were built of ashlar masonry bonded with mortar. On the eastern side of the building there is a splayed door-jamb and a small slit window. On the lakeside wall there is a second slit window.
Though the structure of the building is very simple, as it was built in order to take advantage of the slope and the rock face, the dating is extremely uncertain. Similar structures have been built almost up to present day. However, the first settlement of the island was probably made between Late Roman times and the twelfth century.
The most recent research on these buildings was conducted in 1992 (M. Brambilla, G. P. Brogiolo).