Chandigarh, Dec 27, 2025: India’s oldest mountain system, the Aravalli range, has suddenly become the centre of a national debate after a recent Supreme Court ruling changed how the hills are legally defined.
Last month, the Supreme Court accepted a new definition of the Aravalli Hills proposed by a committee led by the Union Ministry of Environment, Forest and Climate Change. Under this definition, only landforms that rise at least 100 metres above the surrounding terrain will qualify as Aravalli hills. Clusters of such hills within 500 metres of each other will be treated as an Aravalli range.
At first glance, the ruling appears technical. But environmentalists say its impact could be enormous.
The Aravallis stretch across Gujarat, Rajasthan, Haryana and Delhi and are estimated to be around 670 million years old. They act as a natural barrier against the expansion of the Thar Desert, recharge groundwater, regulate rainfall and reduce dust storms in north India.
According to data cited by experts, the Forest Survey of India mapped over 12,000 hill features across Aravalli districts, but only about 1,048 meet the new 100-metre elevation criterion. This means a large portion of low-lying hills and forested areas may no longer qualify as “Aravalli” in legal terms.
Why does this matter? Because areas that fall outside the official definition can be opened up for mining, construction and tree cutting, subject to other laws. Activists warn that what is being redefined on paper could lead to real-world destruction on the ground.
Congress leaders and environmental groups argue that earlier court orders treated the entire Aravalli system, regardless of height, as ecologically sensitive. They fear the new definition breaks the continuity of the range and weakens decades of environmental protection.
That fear has triggered awareness videos, public campaigns and calls to “save the Aravallis,” especially in Delhi-NCR, Haryana and Rajasthan, where mining pressure is already intense.
