Twice a year, tens of thousands of people climb Büyükada's highest hill in near silence, unspooling thread as they go. Aya Yorgi crowns that summit — a small Greek Orthodox monastery dedicated to Saint George, known here as Koudounas, "of the bells," after a legend of a buried icon that rang beneath the earth to be found. Monks have kept a shrine on this hilltop since Byzantine times, by tradition from the tenth century; the church standing today is a plain early-twentieth-century rebuild, raised after fire and neglect. Its terrace looks out over the Sea of Marmara, the other Princes' Islands scattered below.
You reach it on foot. From the square at the foot of the hill, a steep paved path winds up through pine woods, and on ordinary days it stays quiet — a few worshippers, dozing cats, the smell of resin and candle wax. On the two feast days, spring and autumn, that same path fills shoulder to shoulder. Pilgrims of many backgrounds tie threads along the railings, leave wishes and lumps of sugar, and light candles in the small vaulted church. At the top, a garden restaurant pours local wine while the ferries crawl far below.