Climate change, rapid urbanization and industrialization have so far resulted in substantial loss of agricultural land, forestry and green areas that are environmentally of utmost importance. This is noted considerably in many coastal regions and highly populated cities such as metropolis Istanbul in Turkey. In that sense, there is an urgent need for evaluating the magnitude, pattern, and type of land cover/use (LCLU) changes for projecting future land development in the most sustainable manner in this highly crowded city. Remote sensing (RS), in conjunction with Geographic Information Systems (GIS), has been widely applied and recognized as powerful and effective tools of modern technology in detecting LCLU. Five satellite imageries acquired in 1975, 1987, 1997, 2007 and 2014 were classified and corresponding LCLU thematic maps were achieved. The change detection results revealed great loss in the green areas such as forests, and in turn, huge increase in urbanized and industrialized areas. Sharp increases were detected for land cover classes of urban fabric, industrial and commercial units, and for open spaces covered with slight or no vegetation, in ratios of 227%, 410% and 402%, respectively over time. Hence, such quantitative LCLU results of this strategically important region of the world are sufficiently robust to alert urban and regional planners for efficient management practices intending to form a balance between utilization and protection of natural resources.