UNESCO has added an area known as the “Diamond Triangle” of Buddhist sites—Ratnagiri, Udayagiri, and Lalitgiri in Odisha’s Jajpur and Cuttack Districts—to India’s tentative list for possible inscription as World Heritage Sites, according to Indian officials.
The three sites are widely regarded by scholars and archaeologists as significant centers of early and medieval Buddhism in eastern India, and are believed to have supported the development of the three major Buddhist traditions: Theravada, Mahayana, and Vajrayana.
The Archaeological Survey of India (ASI), which serves as the nodal agency for implementing the World Heritage Convention on behalf of the Government of India, prepared and submitted the nomination dossier to UNESCO’s World Heritage Centre eight months ago. The submission was made through India’s ambassador and permanent representative to UNESCO, Vishal V. Sharma.
Earlier this week, UNESCO formally notified Sharma that the nomination of the Diamond Triangle sites had been accepted for inclusion on India’s tentative list. The World Heritage Centre also confirmed that the documentation submitted by ASI met operational guidelines required for tentative listing.
The superintending archaeologist of ASI’s Puri Circle and a key contributor to the nomination process, D. B. Garnayak, explained the significance of the development: “The tentative list identifies sites that are of outstanding universal value, either culturally or naturally, and suitable for potential inscription in the World Heritage List.” (Times of India)
With the tentative listing secured, responsibility now shifts largely to Odisha’s state government to advance the nomination. Garnayak noted that further documentation, conservation planning, and sustained advocacy would be required to move the Diamond Triangle toward full World Heritage status.
Odisha’s Law Minister, Prithiviraj Harichandan, said in a social media post: “Odisha’s diamond triangle; Ratnagiri, Lalitagiri and Udayagiri, have been included in the Tentative List of India by UNESCO for consideration of granting World Heritage Site recognition. This is a matter of pride for our state, our culture and heritage.” (Deccan Herald)
The three sites are located near one another in central Odisha and have long been collectively referred to as the Diamond Triangle due to their archaeological richness. Ratnagiri is traditionally known as the “hill of precious gems,” Udayagiri as the “hill of the rising sun,” and Lalitgiri as the “red hill.” Together, they preserve extensive remains of stupas, monasteries, votive shrines, inscriptions, and stone sculptures depicting the Buddha and a wide range of Buddhist deities.
Among the three, Ratnagiri is considered the largest and most prominent Buddhist establishment. Spread across approximately 7.28 hectares on the Assia hill range along the banks of the Kelua River in Jajpur District, the site has yielded significant archaeological discoveries, including monumental monasteries and finely carved images associated with Vajrayana Buddhism.
India has 70 sites on UNESCO’s tentative list, spanning cultural, natural, and mixed categories. Odisha is already represented on the list by Ekamra Kshetra in Bhubaneswar and Chilika Lake in Ganjam District. In 2025, the Chausathi Yogini group of temples—distributed across multiple Indian states, including Odisha—was also added to the tentative list. Odisha is home to two such Yogini temples, located on the outskirts of Bhubaneswar and in Balangir District.
If ultimately inscribed on the World Heritage List, the Diamond Triangle would join a select group of globally recognized Buddhist heritage sites, further highlighting Odisha’s historical role in the spread and evolution of Buddhism across South and Southeast Asia.
See more
State’s 3 Buddhist sites in tentative list for UNESCO World Heritage tag (MSN)
State’s 3 Buddhist sites in tentative list for Unesco ‘World Heritage’ tag (Times of India)
Odisha lauds inclusion of 3 Buddhist sites in UNESCO tentative list for world heritage site (Deccan Herald)
Buddhist Diamond Triangle Joins UNESCO World Heritage Tentative List (Insights on India)
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