The parts of the monastery preserved today are the catholicon, a section of the cells, and the refectory (Trapeza) at the south-east end of the catholicon. The church is single-aisled with a barrel-vaulted roof, a vaulted narthex, and three exonartheces. The interior is covered with finely executed wall paintings.
The monastery was founded in the Late Byzantine period and reached its highest point of prosperity in the 16th century. The catholicon (main church) was renovated by Michael Philanthropenos in 1291/2 and was later enlarged and decorated with wall paintings, in three phases (in 1531/2, 1542, and 1560, respectively).
Today the church is used only on specific days of the year.
The area of the Island in the Lake of Ioannina was a monastic site during the Byzantine period. Seven more monasteries dating from several periods are preserved on the Island but the monastery of Agios Nikolaos seems to be the most important of all.