Rayalaseema landscape: Preserving the past, securing the future

Across the Rayalaseema region of Andhra Pradesh, fragments of a historically-rich landscape stand amid rocky hills, river valleys, and expanding settlements. Forts that once guarded strategic routes, temples that drew generations of devotees, and monuments bearing the imprint of successive dynasties offer vivid glimpses into the region’s political, cultural, and religious history. Today, however, these sites face severe pressure from quarrying, road construction, and unregulated tourism.

Geologists aptly describe this landscape as a library of deep time, preserving natural events spanning billions of years. Much of Rayalaseema lies within the Cuddapah Basin and the ancient Dharwar craton—one of India’s oldest crustal blocks. Its basement rocks formed more than 2.5 billion years ago during the Precambrian era. Over centuries, sediments accumulated, volcanoes erupted, and layers were buried, folded, and eventually exposed again.

This ancient foundation stands in stark contrast to the young, restless Himalayas, which were born from the collision of tectonic plates and remain seismically active.

Prof. U. Suresh from the Department of Geology at Sri Venkateswara University, Tirupati, explains this profound difference: “The southern heartland of Andhra Pradesh is the weathered, unyielding skeleton of an ancient Earth. Safely sitting on the Dharwar Craton and the Cuddapah Basin, this region was formed 2.5 billion years ago. While the Himalayas strive restlessly toward the sky, Rayalaseema rests in profound structural calm.”

For those who know where to look, this ancient stillness is hidden in plain sight. Along the ghat road up to Tirumala, that mysterious calm is written in stone. Exposed on a steep, dusty road cut that thousands of pilgrims pass without a second glance lies the Eparchaean Unconformity—one of the world’s most significant geological boundaries. Here, light layers of 1.5-billion-year-old Nagari quartzite rest directly on dark, 2.5-billion-year-old Archaean granite. Between them, nearly 800 to 1,000 million years of Earth’s history have vanished. It is a billion-year gap where older rocks were uplifted, eroded to a plain, and buried again.

Further south, the Nagari Hills dominate Chittoor and Tirupati. Their flat-topped profiles are classic mesas—ultra-hard quartzite on ancient granite bases. Formed 1.5 billion years ago, these peaks were strategic lookout posts during the British Raj and the two World Wars. Today they are spiritual sentinels. The sharpest is Nagari Nose, standing at 2,805 feet and visible within a radius of 70 kilometres.

“Devout families from hundreds of villages surrounding the Nagari hills and neighbouring Tamil Nadu revere the peak and perform pujas atop it on every full moon day,” says Ramanuja Chalapathi, a former government schoolteacher and social activist in Nagari.

Now, mining activity is slowly climbing toward the peak, threatening Nagari Nose and other geological wonders—Three-Rocks-Mound (Moodu Ralla Banda) and Bheemuni Palada rock, he says. “Once a ridge is cut, its original structure can never be restored.”