Mangalore International Airport is one of the few airports in India with a tabletop runway. A tabletop runway is basically a runway located on the top of a hill with ends adjacent to steep slopes. Such airports are challenging not only from the take-off and landing points of view but also from the structural perspective. There is a need for massive cutting and filling operations to construct the runway on mountainous terrain. Stabilization of the valley slope requires slope stabilization measures in the form of retaining structures with a greater height. However, the selection of a suitable retention system for the runway expansion was quite challenging due to the vast stretches of laterite-capped hillocks which have an excellent geotechnical property in dry state and inferior properties in wet conditions. Moreover, the proposed retention system should act as a firm foundation and be able to carry the loads of aircraft, other vehicles, and seismic loading. The total height of the retention system on the runway valley side ranged between 40 and 50 m. The fill material consists of a reinforced soil structure at the top (of max. 17 m high) and bottom (of max. 13 m high) and filled slope in between. The filled slope was protected with berms, erosion control measures, and reinforced with geogrids. Special attention was given to the drainage system so as to reduce the pore water pressure behind the reinforced soil structure and to channelize runoff from the slope through appropriate drains. This paper comprises the system details of a steep reinforced soil structure along with drainage measures and erosion control measures adopted for slope stabilization for runway expansion, the design considerations, and corresponding stability checks for safety with respect to the reinforced soil structure and drainage, post-movement observations, forensic analysis of the reinforced soil structure, and redesign proposal for rehabilitation, current status of the project, and conclusions.