UrbanUrban areas around the world are the hub of populationPopulation and built-up infrastructure with varying environmental, political, social and spatial characteristics. The fragmentation in all these due to rapid unplanned urbanizationUrbanization puts significant pressure on natural resources. This creates serious issues for the ecological capacity of cities, particularly in Global South. This unplanned urbanUrban expansion challenges the urbanUrban sustainabilitySustainability, and past studies proved this phenomenon. This study makes an attempt to review the past literature and ground investigation of the issues regarding the urbanUrban sustainability, populationPopulation, developing countries, and urbanizationUrbanization. After deep examination of the past literature from world reputed international journals, government documents World Bank reports, and books the study extract the results. This comprehensive review found that the unplanned urbanizationUrbanization, rapid populationPopulation growth, spatial inequality of urbanUrban land use, urbanUrban land use fragmentation are challenging tasks to ensure the city infrastructure, developmentDevelopment and ensure sustainabilitySustainability for provision of services to locals. The results of the study can be used for city planning and developmentDevelopment for future and forceful tools for infrastructure developmentDevelopment, urbanUrban land use and spatial homogeneity.