Monastery of Agios Ioannis Kareas, Byzantine monastery in Kareas, Greece

The Monastery of Agios Ioannis Kareas stands at 490 m on the western slopes of Mount Hymettus, near the Kara quarries in the Municipality of Vyronas. Its old catholicon is a cross-in-square church with a dome on four columns, built in the last quarter of the 11th century. Wall paintings survive only in the prothesis; an old inscription on the floor to the right points to a possible Early Christian prayer house.

Founded probably in the 4th century, as a surviving tombstone inscribed "NEIKAGORIS DIAKONISSIS" indicates, the monastery was a patriarchal stavropegion dedicated to Saint John the Baptist. It was abandoned in 1673; the first known date is 1575, when it was probably renovated. The present church was built in the last quarter of the 11th century.

The monastery is dedicated to Saint John the Baptist and was formerly a metochion of the Petraki Monastery in Athens, which houses the Holy Synod of the Church of Greece. Since 1972 it has been a sovereign and independent women's community, so the resident community is now female.

The monastery stands at 490 m on the western slope of Mount Hymettus, in the Vyronas municipality, near the Kará quarries; the approach is uphill on foot. The old catholicon is entered from its surrounding courtyard, and the floor inscription lies to the right inside the nave.

The monastery was a metochion (dependency) of the Asomaton Koukoupoulis Monastery in Athens, while the Bulgarian source records it as a former metochion of the Petraki Monastery, where the Holy Synod of the Church of Greece sits. Since 1972 it has been a "sovereign and independent women's communal monastery".