English: Tuman was the first capital of the Kalachuris of South Kosala – also known as the Haihayas. Inscriptions and Sanskrit literature suggest that this Hindu dynasty had built major temples in Tuman by the 9th-century, whose history dates at least to the 6th century. Later inscriptions mention the many temples of Tuman. Of these, only one ruin – the Mahadeva temple – had survived in the 19th-century. In early 21st century, excavations of mounds led to the discovery of ruins of twenty more temples in Tuman along with notable artwork for Shaiva, Vaishnava and Shakta traditions of Hinduism.

The main temple of what is now called Mahadev temple group faces west. It stands on a molded jagati, has a mandapa and a square plan garbhagriya. The sanctum entrance is ornate, is flanked by Yamuna and Ganga goddesses, and has a Shiva linga. The lintel features Brahma, Vishnu and Shiva, along with various avataras of Vishnu. The latter artwork suggests that it may have been a Vishnu temple, or that the complex of temples at this site was dedicated to Vishnu. After the site was destroyed, it went into disuse for many centuries, then reclaimed by regional Hindus who installed a Shiva linga.

The site has many more temple platforms, numerous broken and mutilated Hindu artwork (defaced, beheaded statues, chopped limbs). The notable artwork found here include Surya, Narasimha, Gajalakshmi, Vasudeva, Ganesha, Durga, Hanuman and kama-mithuna scenes (erotic couples).