It is obvious to anyone working on or dealing with underground mining operations, production gaps have to be opened in the ground during mining. The ground layers just above these gaps collapse toward production lines resulting in horizontal and vertical movements both inside and on the earth's surface. These movements are referred to as mining subsidence which eventually causes technical, economic, social and environmental hazards to natural and cultural structures on the surface. It is substantially crucial to the general and regional characteristics of these subsidence occurrences in the underground mining region so it can be possible to mitigate the subsidence induced damages and problems both in the ground and on the surface. Subsidence observations, thus, are conducted inside and on the ground by employing geodetic, geophysical and geotechnical methods with the aim to determine the characteristics and parameters of subsidence occurrence in a region evaluating these subsidence observations. The Zonguldak Hard Coal Basin and Kozlu Coal Production Region within the basin are places where urbanization and underground mining operations are intensively under way. Therefore it is vitally important to continuously monitor the horizontal and vertical displacements formed due to the underground mining in the basin and to determine the subsidence parameters so that it may be possible to forestall the subsidence induced issues that may occur in the near future. This study yields information and computations about the subsidence parameters determined under the light of three periods of geodetic observations carried out in the region. Using the three periods of GPS and precise leveling observations, the average slope angle values resulting from vertical displacements in the study region were obtained from the adjusted coordinates and height differences, and estimated as 16 ''.67 in positive (+) direction and 18 ''.03 in negative (-) direction. The horizontal unit deformation parameters, on the other hand, were computed as 0.28 mm/m for the extension parameter while 0.26 mm/m for compression parameter along the routes chosen in the Kozlu region. (C) 2012 Elsevier Ltd. All rights reserved.