It is a one column basilica with cupola, built in the Lower Town of the Castle during the second Venetian rule (1690-1715). It was during this period that it was transformed to a two column basilica.
According to local tradition, it was founded by the Monemvasiot bishop of Kythera island, Filotheos Darmarios. The worship of Our Lady Myrtidiotissa is indeed related to the island of Kythera, since it shared trade and cultural links with the Castle of Monemvasia. The church is also known as “Our Lady Kritikia” (Our Lady from Crete) because of Cretan refugees that settled in Lower Town.
The church is famous for its gilt wood-carved iconostasis with its prominent Renaissance characteristics of the 16th century, which was taken from the Church of the Elkomenos Christos where it originally belonged. Structural features of the church such as the round skylights, the facade pediment and other ornamental details indicate the influence of Western architecture.