Abstract: On 17 March 2005, a large and complex landslide occurred west of Koyulhisar (Sivas, Turkey). This landslide, mostly comprising debris derived from volcanic rocks and mud flow, moved over the Kuzulu settlement area in the valley in a very short time and 15 people were killed. The Kuzulu landslide zone is not a simple mass movement limited to a single movement. Instead, complexities are introduced by the regional topographic structureand location of the crown and heel zone so that at least 4 other large flow movements occurred in this region between 17 March 2005 and August 2007. One of the most important factors initiating and accelerating this landslide hasbeen the influence of surface and groundwater seep age from melting snow. This seepage has followed the densepattern of discontinuities and normal fault planes observed in and around the crown region. These waters saturated the profoundly altered volcanic bedrocks with water, and as a result, a slip surface developed between the underlying limestone and weathered volcanic rocks. This was responsible for the catastrophic mass movement.To correctly interpret the causes and consequences of mass movements, where the movement speeds and directions can be monitored in detail using the advanced technological tools available today, detailed geological mapping is essential. There are currently differing interpretations of the development and triggering factors responsible for the Kuzulu landslide. This is primarily because the geological and tectonic structure of the landslide zone and its surroundings have not hit her to been investigated in the necessary detail.In this study, a detailed new geological map revealing the basic geological features of the region has been compiled and the characteristics of the landslide re-evaluated for comparison with previous studies. With the help of Digital Elevation Model (DEM) maps created from the satellite images of the Kuzulu Landslide area before and after the landslide, a total volumetric movement of 10.367.766 m3 is estimated to have occurred. We calculate that anet 9,372,880 m3 of material flowed from the area within the landslide boundary. Any assessments of ground suitable for settlement with a view to urban development and planning requires aproper understanding of the geomorphological structure of the surrounding region and the engineering geologicalproperties of the ground. The fact that Koyulhisar district centre is located both in the immediate vicinity ofan active fault zone such as KAFZ and on an active landslide area emphasises this issue. Detailed geological, geomorphological, landslide susceptibility, hazard and risk maps are of great importance to prevent / mitigate the damaging consequences of earthquakes and the landslides that they may be motivated