The Monastery of Osias Theoktisti is located in Pigi village, near Kampos, on the north side of the island. It is a monastery dedicated to the Blessed Theoktiste from Molyvos, Lesvos, who according to tradition, is connected to Paros and Ikaria.

It is not known exactly, when the monastery was built, but an inscription on it, indicates that the monastery operated in 1688, when its hagiography took place. Today, no monks live in the monastery.

From an architectural standpoint, the monastery consists of: the Catholic (i.e. the main temple where all the monks were gathered), fifteen cells that work as hostels and various auxiliary spaces. The Catholic architectural belongs to the type of aisled, barrel-vaulted basilica and has several murals.These murals refer to Cretan painting. Tradition says, that the painter Pantelis Hatzis, reader from Chios and one assistant of him, took the painting up to the monastery.

A little further from the main temple, you can visit the Chapel of Theoskepasti, formed in an impressive way, inside a cave, which on top is covered with a rock. Perhaps one of the most impressive chapel in the world!According to local tradition, the inhabitants carried the remains of Osias Theoktistis from the Catholic sanctuary, inside the cave and formed the area as a chapel. Inside the cave old carved iconostasis is preserved, dating from around 1894.