Regionalisation is the process of dividing a large geographical area into smaller regions based on common characteristics. In the study of Regional Geography of India, physical bases of regionalisation are among the most important criteria because they provide a natural framework for understanding the diversity of landscapes, resources, climate, and human activities. Physical factors influence settlement patterns, agriculture, transportation, economic development, and cultural practices. Therefore, the identification of regions on the basis of physical characteristics helps in scientific planning and balanced regional development. Relief is one of the primary physical bases of regionalisation. Variations in topography create distinct geographical regions with unique environmental conditions. India can be divided into the Himalayan Mountain Region, the Northern Plains, the Peninsular Plateau, the Indian Desert, the Coastal Plains, and the Islands. Each of these regions differs significantly in terms of elevation, slope, geological structure, vegetation, and land use.