Some 17,000 people died then, including 1,000 in Istanbul.
This is the second powerful earthquake to hit Turkey this year, after one in the eastern city of Elazig killed more than 30 people in January.
The tremor was felt as far away as Athens and Istanbul.
On the Greek island of Samos, which is home to a large migrants camp, the civil protection agency described the situation as “extremely difficult”.
“Churches, ports and houses will be rebuilt. With the help of God and men,” said Priest Emmanouil, whose church in the island village of Pythagorio was damaged. “But lost souls do not return.”
Turkey reported around 550 aftershocks following the quake, including 35 that were above four in magnitude.
Rescuers had not lost hope, but a sense of peril hung over the coastal province, with large cracks and broken plaster lining buildings that looked like they could fall from another bad shake.
In Bayrakli’s city centre, families wept and prayed at the first funerals for the victims of the quake.
“I can’t cry anymore. Look I’m not crying,” one woman wailed. “Mother, when will I see you again?”