Sümela is a Greek Orthodox monastery welded to a cliff 300 metres above the floor of the Altındere valley, with only forest and air beneath its balconies. Its name comes from the Greek melas, black — after the mountain that holds it, Karadağ, whose Turkish name means the same. Tradition credits two monks from Athens, Barnabas and Sophronios, who founded it around AD 386 after finding an icon of the Virgin in a cave here. Its real patron came a thousand years later: Alexios III of Trebizond, whose 1365 decree gave it revenues, tax exemption and imperial protection. The Ottomans took Trebizond in 1461 and renewed those privileges rather than revoke them; the cave shrine grew into a warren of chapels, cells, a kitchen and a library stacked against the rock.
The last stretch is on foot, up a steep cobbled stair through spruce and chestnut forest. This is one of the wettest corners of Türkiye: damp air off the Black Sea condenses against the cliff, and the building can vanish into cloud within minutes. At its centre is the Rock Church, a cave painted inside and out, its frescoes lying in layers from three periods. Look at the lower saints: many have had their eyes scratched out, and names are scrawled across the paint. Abandoned in 1923 in the Greek-Turkish population exchange, the monastery lost its wooden floors to a fire in 1930 and stood unguarded for decades; restorers now lift the graffiti in colours close to the originals. Rockfalls closed the site in 2015; engineers pinned the cliff above with steel cable and mesh, and it reopened in full on 1 July 2021, drawing half a million visitors in 2025. An Orthodox liturgy has been held here since 2010, though for three years running permission has come for late August, not the 15th — the feast day itself.