The Greek–Turkish earthquake diplomacy was initiated after successive earthquakes hit both countries in the summer of 1999 and led to an improvement in Greco-Turkish relations. The so-called arthquake diplomacy generated an outpouring of sympathy and generous assistance provided by ordinary Greeks and Turks in both cases. Such acts were encouraged from the top and took many foreigners by surprise. They prepared the public for a breakthrough in bilateral relations, which had been marred by decades of mutual hostility.
On August 17, 1999, at 3:02 am, Turkey experienced a very large earthquake centered around the Gölcük and Arifiye areas in Adapazarı. The most severely affected area was the industrial city of İzmit. The İzmit earthquake registered 7.6 on the moment magnitude scale, lasted for 45 seconds, and had a maximum Mercalli intensity of IX (Violent). The official number of casualties was about 17,000, although the numbers could be above 35,000. Three-hundred thousand people were left homeless and the financial cost is estimated at about 3 billion dollars. Turkey's largest city, Istanbul, was also affected with many buildings damaged and deaths amounting to dozens of people. The rupture passed through major cities that are among the most industrialized and urban areas of the country, including oil refineries, several car companies and the navy headquarters and arsenal in Gölcük thus increasing the severity of the life and property loss.
The main characteristic of this particular human crisis was the difficulty of the Turkish authorities to apply any rational planning because of the magnitude of the disaster, and the fact that the majority of the Greek initiatives were undertaken not only by the government, but mainly and most importantly by local authorities, NGOs and individuals.