This is a detailed review of the landslides in the hilly areas of the state of Tamil Nadu and especially Nilgiris areas, the cause, distribution, effects and the current methods of mitigation. Geomorphological conditions (slope gradient, geology, soil composition), hard monsoon rains and human activities like deforestation and development of infrastructural facilities are the major causes of landslides. GIS-based susceptibility analysis based on techniques such as Analytical Hierarchy Process (AHP), logistic regression, neural networks, and fuzzy logic has classified almost 50% of Nilgiris as medium to very high risk. There were documented landslide incidences in 1902, 1978–79, 1993, 2009, and afterward in Cyclone Gaja in 2018, which led to infrastructure damage, loss of lives and degradation of the environment. But mainly missing are obsolete hazard maps, limited field validation, and no real-time monitoring and early-warning systems. We suggest revising zoning maps with high-resolution data confirmation, introducing real-time sensors, enhancing slope stability by geotechnical examinations and training the community. These measures are necessary to mitigate vulnerability to landslides and encourage safe development in Tamil Nadu business sensitive areas.