This comprehensive review examines the intricate aging processes occurring in sanitary landfills, synthesizing insights from eight key studies. It illuminates the nuanced aspects of aging by delving into the physical, chemical, and mechanical changes within landfills. The results from these studies emphasize the dynamic nature of these alterations, providing valuable guidance for future waste management strategies. This analysis represents a significant stride towards fostering an environmentally sustainable future. Globally, municipal solid waste (MSW) landfills serve as primary solutions for MSW disposal. However, characterizing the geotechnical properties of MSW presents a challenge due to its diverse composition, varying particle sizes, and continuous degradation. A profound comprehension of these geotechnical attributes is crucial for the planning and functioning of landfill facilities. Regrettably, detailed information on the geotechnical characteristics of MSW in landfills is limited. The selection of appropriate MSW material properties stands as a pivotal aspect of landfill design. This research underscores the imperative need for innovative methods to comprehensively assess landfill aging, recognizing the multifaceted nature of physical, chemical, and mechanical transformations. The incorporation of technology is pivotal, with studies advocating the utilization of advanced tools like remote sensing and geospatial analysis for effective monitoring and management of aging landfills. Embracing such a progressive approach is essential to tackle the challenges posed by landfill aging and to advance sustainable waste management in the future.