Aya Yorgi is a small Greek Orthodox monastery on the highest hill of Büyükada, an island an hour or more out from the city by ferry. From the square at the foot of the hill a steep paved path winds up through pine woods, twenty to thirty minutes of climbing to a summit at just over two hundred metres. On ordinary days it stays quiet: a few worshippers, dozing cats, the smell of resin and candle wax. The church itself is a plain early-twentieth-century rebuild, and its terrace looks out over the Sea of Marmara with the other Princes' Islands scattered below.
Twice a year, on 23 April and 24 September, that same path fills shoulder to shoulder with tens of thousands of people climbing to the top. Monks have kept a shrine on this hilltop since Byzantine times, by tradition from the tenth century. Saint George is the dedication, and Istanbul knows the place by his local name, Koudounas. On an ordinary weekday you may have the terrace to yourself.