The church is built in the centre of Petra (55 km from Mytilene, in the north part of the island) on a rock of approximately 40m height. 114 steps carved in the rock lead to its top. It constitutes one of the most important places of pilgrimage on Lesbos.
Travelers from the 15th to the 18th century report the existence of a small castle on the top of the rock. It is probable that in an earlier phase there was a small church surrounded by walls, which in the beginning of the 17th century was replaced with a bigger one which took its present form after the repair works in 1840. This church is made of stone and follows the architectural type of a three-aisled basilica.
Its interior is decorated with a remarkable wood carved templon as well as a wood carved bishop's throne.