According to figures provided by the Prime Ministry's Disaster and Emergency Management Authority (AFAD), two-thirds of the population in Turkey live in regions under the risk of potential earthquakes. Turkey sits on three active fault zones running through the north, east and Aegean Sea whose total length is 2,900 kilometers, in addition to many smaller fault lines traversing the country. Over 33 million people live in regions under the risk of an earthquake of a high magnitude while some 23.3 million people inhabit regions exposed to the risk of earthquakes of lesser magnitude. Overall, they make up two-thirds of the total population, which currently stands at 77.6 million.AFAD figures show 10 million buildings are situated in high risk areas and another 5 million are in secondary risk areas. The most active fault line, in the country's north, caused a major earthquake in 1999, killing tens of thousands of people in northwestern Turkey.Years after the disaster, Turkey has seen an overhaul of measures against earthquakes such as compulsory earthquake insurance and campaigns to raise awareness about the disaster to inform the public. More importantly, the government undertook the ambitious project of urban transformation. Old, crumbling buildings across the country are being demolished to make way for new earthquake-proof buildings. Though it is difficult to entirely change the course of urbanization and housing that led to haphazard development, especially in big cities decades ago, the country has gradually renewed infrastructure through this project. According to the Ministry of Environment and Urban Planning, there are 42,000 risky buildings in the country that will be "transformed" into contemporary, safe buildings. Measures are more or less in place, but the country is still prone to a major earthquake. Istanbul, a city of 14 million people, is at the heart of concerns. Experts warn that about 30,000 buildings in the city will be either heavily damaged or completely demolished in the case of a large-scale earthquake, dubbed the "great Marmara earthquake," after the region where Istanbul and other big cities are located whose likelihood is high at some point in the future.