Urbanization has been the central demographic trend, not only in the Asia-Pacific region, but also for the entire world. Local geo-mapping is the vital tool for analyses of land-use and land-cover. This study attempts to classify land-use in unsupervised settings and create land-cover map by using open-source Landsat data integrated with GIS technologies and other ancillary resources. This work concentrates on Gazipur Sadar (an upazila or sub-district of the Gazipur District in central Bangladesh, part of the Dhaka Division) and Kaliakair, which are rapidly growing unplanned urban and industrial zones. The usage of python coding greatly assisted accomplishing the post-classification change detection analysis. Accurate assessment of urban growth and the spatiotemporal changes in land-use are becoming a routine practice for understanding urban dynamics and environmental impacts. Current research quantitatively examines the changes in land-use/land-cover and urban expansion in study areas. Gazipur is a growing metropolitan city north of the capital city of Dhaka in Bangladesh. The area experienced rapid industrialization followed by unplanned urbanization. In over two decades, Gazipur recorded an increase in urbanization (44.16%) with a decrease in forest areas (20.87%) and water bodies (5.88%). Meanwhile during the last five years, Gazipur had an accelerated change with an increase in urbanization (28.03%), a decrease of forest areas (26.29%) and water bodies (8.92%). This caused an environmental imbalance, a land-use pattern change, topsoil degradation, and habitat destruction. There has been a major change in vegetation pattern since 1991. The findings of this study and the geospatial information generated from the land-use mapping can be used as an important baseline reference for planners, policymakers, stakeholders, and other relevant interested groups in Bangladesh to contemplate multi-disciplinary planning and remediation measures to conserve finite land resources.