During Venetian rule, a situation different from the rest of Crete took shape in Mylopotamos, due to the action of the powerful aristocratic family of the Kallergos. Alexios Kallergis organized a revolution against Venice and in 1299 signed a treaty with the Venetians, with which he opened the way for Cretan nobility, i.e. for the granting of titles of nobility by Venice to Cretans and not only to Venetian aristocrats. At the same time, he succeeded in establishing an Orthodox diocese in Mylopotamos. The seat of the Kallergi family was in the fortress in “Apano Kastri”. Above Kastri, in a rocky fortress, the architectural remains of the medieval fortress, “Apano Kastri” or “Apano Kasteli”, are preserved. The fortress, as mentioned by Lorenzo De Monacis in his chronicle, was founded by the Kallergi family. This area was chosen by Alexios Kallergis, in the 13th century, as a place of residence and a base for battles against the Venetian and Greek competitors. The name of the settlement is due to this fortress.
