Palaiokastro/Mavri Rahi is in the southwestern end of Psara.

Paleokastro protected the western side of the harbor of Psara. During the revolution of 1821, cannons and fortifications were installed here by the residents, turning it into a fortress to defend the island. The last act of resistance was here, during the Turkish invasion in June 1824. The last defenders of the island defended it vigorously and when the Turks finally broke the last line of defense, they decided to set fire to the powder keg and blast themselves, preferring a heroic death from captivity and slavery.

Today in Palaiokastro/ Mavri Rahi you will find a simple monument in honor of its defenders and some remains of the fort's walls. It is definitely worth a visit to pay tribute to the heroic people of Psara, as did the national poet Dionysios Solomos through his lyrics:

"At the full black ridge of Psara/ Glory walks alone/ studying the brilliant lads /she wears a wreath upon her hair /made from few ripe herbs /that were left in the wasteland."