Abstract: An earthquake taken place on the western part of the North Anotolian Fault Zone around Bolu, Düzce and Kaynaşlı villages on the 12 November 1999 at 1857. The earthquake affected very large areas resulted in more than 800 deaths, left over2500 people wounded, around 1500 buildings damaged. It is notable that Bolu tunnel and viaducts were also severely damaged. According to USGS data, epicenter of the Duzce earthquake falls at 40.768 North latitude and 31.148 East longitudewhere coincides N-NE of the Çınarlı Village of Düzce. The magnitude was determined as 7.2 Ms and started at 14 km deepfrom surface. This event created about 30 km surface rupture between Gölyaka in the west and Dip village in the east. Theobserved dextral strike-slip displacement yields up to 380 cm along the eastern part of the surface rupture. The detailed mapping of surface rupture revealed at least one main and two smaller segments in a E- W trend. In addition to strike-slip offset,occasionally huge landslides of around 4-5 m, collapsed and subsided. The geometry of the surface rupture of the Düzce earthquake, elongated between Gölyaka and Dip villages, has shown a general characteristics of strike-slip faulting such as anastomosing structures, horse tails, pressure ridges and sag ponds were extensively developed along the surface rupture of Düzceearthquake. Furthermore, small scale sag ponds and liquefaction structures were determined locally along the surface rupture.