Eastern Ghats

The Eastern Ghats form one of the two flanking highland systems of the Indian Peninsula, the other being the Western Ghats. They are an ancient, structurally complex chain of hills extending roughly 1,750 kilometres along the eastern margin of the Deccan Plateau, running south-west to north-east through Odisha, Andhra Pradesh, the northern fringe of Tamil Nadu, and a small portion of Karnataka, before merging with the Western Ghats near the Nilgiri Hills. Geologically they belong to the Eastern Ghats Mobile Belt, a Precambrian orogenic terrain composed largely of charnockites, khondalites, granitic gneisses, and metamorphic rocks, indicating a far older and more deformed crustal history than the relatively younger volcanic and basaltic edifice associated with the Deccan Traps to the west. For UPSC General Studies Paper I (GS1) physiography, the Eastern Ghats are treated as a residual, much-denuded relief feature rather than a continuous wall.

The defining structural characteristic of the Eastern Ghats is their discontinuity. Unlike the Western Ghats, which present an almost unbroken escarpment, the Eastern Ghats are repeatedly breached and dissected by the large east-flowing peninsular rivers—the Mahanadi, Godavari, Krishna, and Kaveri—which cut transverse gaps as they descend from the Deccan Plateau to drain into the Bay of Bengal. These river valleys fragment the range into isolated hill blocks, plateaus, and detached ridges separated by broad alluvial corridors and deltaic plains. The mean elevation of the Eastern Ghats is around 600 metres, considerably lower than the Western Ghats, a consequence of prolonged erosion acting on an old land surface and the absence of a single continuous tectonic uplift along the eastern coast.

Regionally the system is conventionally divided into a northern and a southern section. The northern Eastern Ghats, lying between the Mahanadi and the Godavari in Odisha and northern Andhra Pradesh, are the highest and most continuous portion; here lie ranges such as the Maliya and Madugula Konda, and the highest peaks of the system, including Arma Konda (also rendered Jindhagada Peak), Sinkram Gutta, and Devodi Munda, all exceeding 1,600 metres. South of the Godavari the range becomes far more broken, with detached massifs such as the Nallamala, Velikonda, Erramala, and Palkonda ranges in Andhra Pradesh, and the Shevaroy (Servarayan), Javadi, and Kalrayan hills in Tamil Nadu. The Nilgiri Hills, where the two Ghat systems converge, mark the southern terminus and contain Doddabetta, the highest point of the broader meeting zone.

In contemporary administration the Eastern Ghats traverse multiple states and have become a focus of resource and conservation policy. The bauxite-rich plateaus of the Niyamgiri and Anantagiri hills in Odisha and Andhra Pradesh, the iron-ore and manganese deposits of the region, and the limestone and gemstone occurrences make the belt economically significant. The Niyamgiri case—decided in part through the Supreme Court of India's 2013 ruling requiring the consent of Gram Sabhas (village councils) under the Forest Rights Act, 2006—became a landmark instance of indigenous and tribal communities (the Dongria Kondh) blocking a bauxite mining project. The Araku Valley, Visakhapatnam Agency areas, and the Koraput plateau remain demographically important tribal regions whose livelihoods and forest rights intersect directly with the Ghats' ecology.

The Eastern Ghats are frequently contrasted with the Western Ghats, and the distinction is examined in nearly every physiography syllabus. The Western Ghats are higher, continuous, run almost parallel and close to the Arabian Sea coast, form the watershed of the peninsula, and receive heavy orographic monsoon rainfall on their windward (western) flank; they are a UNESCO World Heritage Site and a recognised biodiversity hotspot. The Eastern Ghats are lower, discontinuous, lie further inland from the coast, are crossed by major rivers rather than giving rise to them, and lie largely in the rain-shadow with lower and more seasonal precipitation. They should also be distinguished from the coastal plains—the Northern Circars and the Coromandel Coast—that separate the hills from the Bay of Bengal, and from the Deccan Plateau which they bound on the east.

A recurring point of analytical and ecological controversy is the biodiversity status of the Eastern Ghats. Though not formally listed among the world's biodiversity hotspots in the way the Western Ghats are, the range harbours significant endemic flora, sacred groves, and dry deciduous and moist forests, and ecologists have argued for stronger conservation given accelerating mining, deforestation, and fragmentation. Climate vulnerability, encroachment, and the legal tension between mineral extraction and the Forest Rights Act continue to generate litigation and policy debate. The cyclonic exposure of the adjacent east coast and the role of the Ghats in shaping local rainfall and river regimes add further contemporary relevance.

For the working civil-services aspirant and the geography practitioner, the Eastern Ghats are most usefully grasped as a teaching example of denudation, structural discontinuity, and river-controlled relief. Examination questions commonly demand precise comparison with the Western Ghats, identification of constituent ranges and peaks, the rivers that breach the system, and the resource-and-rights conflicts—Niyamgiri foremost—that play out across the belt. Mastery requires holding together the geological antiquity of the mobile belt, the physiographic facts of elevation and orientation, and the live policy questions of mining, tribal rights, and conservation that make the Eastern Ghats more than a static line on a relief map.