1668 North Anatolia earthquake

The 1668 North Anatolia earthquake was a very powerful earthquake that struck northcentral Anatolia in the Ottoman Empire (today Turkey) on August 17, 1668. The exact hour of the earthquake is not known, but it happened in late morning. It had an estimated magnitude between 7.8–8.0 and the maximum felt intensity was IX ("Violent") on the Modified Mercalli intensity scale. The epicenter of the earthquake was on the southern shore of Ladik Lake, southwest of Samsun. 
When the earthquake struck, a 600 km long segment of the North Anatolian Fault ruptured, which caused severe shaking along this entire segment and widespread heavy damage from at least Bolu in the west to Erzincan in the east. It resulted in about 8,000 deaths. The aftershocks continued for 6 months. It remains the most powerful earthquake recorded in Turkey.
Damage.
The town of Bolu was reported to be almost completely destroyed by the earthquake, with 1,800 deaths. There was also severe damage further east along the fault, with another 6,000 reported deaths between Merzifon and Niksar. The total death toll was around 8,000. Some damage was also reported from as far east as Erzincan and at various locations along the Black Sea coast. The town of Samsun was also heavily damaged. The walls and towers of Samsun Castle were damaged and some parts of the structure "were demolished".