Salkhan Fossils Park

Salkhan Fossils Park, officially the Sonbhadra Fossils Park, lies close to Salkhan village, on the SH5A state highway in Sonbhadra district, about 12 km from Robertsganj. Spread over some 25 hectares of the Kaimur Range beside the Kaimoor Wildlife Sanctuary, it is looked after by the state forest department. Its fossils, chiefly algae and stromatolites, are close to 1.4 billion years old, from the Mesoproterozoic era, and rank among the earliest evidence of life on Earth.

The fossils show up as rings on boulders in five separate patches across the park. John Bicknell Auden, a geologist with the Geological Survey of India, recorded the site in 1929, and other researchers followed. After a 2001 newspaper article drew attention to it, the district magistrate formally opened the park on 8 August 2002. Canadian geologist H.J. Hoffman, at a workshop held that December, said he had seen such clear fossils nowhere else. In 2025 the site was added to UNESCO's tentative World Heritage list.