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Context:
- The Supreme Court of India on 20 November 2025 accepted a new definition of the Aravalli Hills, following government panel recommendations.
- Previous definitions included hills and slopes of lower elevation; the new definition focuses only on hills ≥ 100 metres above local relief, along with their adjacent slopes.
About Aravalli Hills
- Geography: One of the oldest mountain ranges in India, stretching approximately 692 km across Rajasthan, Haryana, Delhi, and Gujarat.
- Formation: Dates back over 1.5 billion years, making it among the world’s oldest fold mountains.
- Ecological Significance:
- Acts as a wind and dust barrier, preventing desertification from Thar Desert.
- Helps in groundwater recharge and sustains rivers and wells in surrounding areas.
- Provides habitat and corridors for wildlife, supporting biodiversity.
- Moderates micro-climate and improves air quality near urban-industrial regions.
- Economic Importance: Source of minerals (marble, quartz, copper, lead, zinc) and contributes to tourism and agriculture.
Key Changes
| Aspect | Old Definition | New Definition |
|---|---|---|
| Elevation | Hills ≥ 20 m above surrounding terrain | Hills ≥ 100 m above local relief |
| Coverage | 12,081 mapped hills (20 m+) | 1,048 hills (~8.7%) |
| Legal Status | Protected under environmental laws | Only ~8.7% retain “Aravalli Hill” status; ~90% lose protection |
| Implication for Land Use | Restricted mining & construction | Large-scale areas now potentially open for mining, real estate, and development |
Major Hill Ranges in India
| Hill Range | Location (States) | Highest Peak (m) | Significance |
|---|---|---|---|
| Aravalli Hills | Rajasthan, Haryana, Delhi, Gujarat | Guru Shikhar (1,722) | Oldest fold mountains, prevent desertification, groundwater recharge |
| Vindhya Range | Madhya Pradesh, Uttar Pradesh, Bihar | Sad-bhawna Peak (~752) | Cultural divide N/S India, source of rivers like Betwa |
| Satpura Range | Madhya Pradesh, Maharashtra, Chhattisgarh | Dhupgarh (1,350) | Dense forests, tribal settlements, rich biodiversity |
| Western Ghats | Maharashtra, Goa, Karnataka, Kerala, Tamil Nadu | Anamudi (2,695) | UNESCO heritage site, biodiversity hotspot, origin of Godavari, Krishna, Kaveri |
| Eastern Ghats | Odisha, Andhra Pradesh, Tamil Nadu | Arma Konda (1,680) | Discontinuous, mineral-rich, origin of rivers like Mahanadi |
| Himalayas | J&K, Himachal Pradesh, Uttarakhand, Sikkim, Arunachal | Kangchenjunga (8,586) | Young fold mountains, glaciation, climate barrier |
| Shivalik Hills | Foothills of Himalayas (Punjab, Haryana, HP, Uttarakhand, Sikkim) | — | Youngest mountains, all |