How the Supreme Court’s new definition of the Aravalli redraws the landscape of India’s oldest hill range

LAST MONTH, the Supreme Court in In Re: Issues relating to definition of Aravali Hills and Ranges (2025) accepted a definition recommended by a committee spearheaded by the Union Ministry of Environment, Forest and Climate Change (‘MoEFCC’). The Court held that only landforms rising at least 100 metres above the local relief would qualify as Aravalli Hills, and that clusters of such hills located within 500 metres of each other would form an Aravalli Range. The Forest Survey of India has reported that of 12,081 hills mapped across multiple states, only 1,048 (8.7 percent) meet the 100 metres criterion. This has alarmed several experts.

The Aravallis, stretching across Gujarat, Rajasthan, Haryana and Delhi, are a living ecological infrastructure and the oldest hill range in the Indian subcontinent. The range, estimated to be around 670 million years old, acts as a natural barrier slowing the spread of the Thar Desert, stabilising micro-climates, and recharging aquifers. 

Why the definition of the Aravallis became a question for the Court 

The Supreme Court had been seized of the issue of mining in the Aravalli range through two long-standing environmental matters: M.C. Mehta v. Union of India (1985), within whose mandate the Court was monitoring mining activities in the Aravallis in Haryana, and T.N. Godavarman Thirumalpad v. Union of India (1995), within whose mandate the Court was monitoring mining activities in the Aravallis in Rajasthan. During the hearing of the latter in January 2024, questions arose about whether certain mining operations fell within the Aravalli Hills or beyond them. Different states used different definitions of what constituted the Aravalli Hills and Ranges, and in some cases, such as Haryana, there was no official definition at all. 

This accentuated the need for a clear and consistent demarcation, crucial for regulating mining and protecting the environment. The absence of a clear definition led to incertitude over where mining could legally occur which further made enforcement of environmental safeguards difficult and enabled illegal mining activities. To address this, on May 9, 2024, the Supreme Court directed the constitution of a multi-agency committee, including MoEF&CC, State Forest Departments, Forest Survey of India (‘FSI’), Central Empowered Committee and Geological Survey of India to finalise a uniform definition. 

Following delays, the Committee submitted its report in October this year where it proposed an elevation-based definition. The definition includes a landform with 100 metres or more elevation above local relief qualifies as an Aravali Hill; and a group of hills within 500 metres of each other constitutes an Aravali Range.