The Agios Ioannis Theologos Monastery lies on the western slope of Mount Hymettus, just above the Papagos cemetery. Surrounded by a rectangular enclosure is the four-column, cruciform church.

For years, archaeologists have debated the exact age of the monastery. Some believe that construction began in the 12th century and continued until the early post-Byzantine era, while others think it was built much later, in the 17th century. With valid arguments supporting both sides, the debate has yet to be settled.

Frescoes preserved in various parts of the catholicon have proved to come from the post-Byzantine era. Situated at the western part of the catholicon – the monks’ preserved refectory, complete with pantry and hearth – also dates to post-Byzantine times.