Pusphagiri (Also Puspagiri Mahavihara), one of the earliest buddhist mahavihara spread across Cuttack and Jajpur district, Odisha (ancient Kalinga) in 3rd century AD,   flourished until the 11th century in India. Today, its ruins lie atop the Langudi hills, low hills about 90 km from the Mahanadi delta, in the Jajpur and Cuttack district in Odisha. The actual mahavihara campus, spread across three hilltops, contained several stupas, monasteries, temples, and sculptures in the architectural style of the Gupta period. The Kelua river, a tributary of the Brahmani river of Odisha, which flows to the north east of Langudi hills, provided a picturesque background for the mahavihara. The entire mahavihara is distributed across three campuses on top of the three adjoining hills, Lalitgiri, Ratnagiri, and Udayagiri.
Puphagiri ranks as one of the primary institutions of higher learning in ancient India, along with Nalanda, Vikramshila and Takshila universities. The famous Chinese traveller Xuanzang (Huien Tsang) visited Puphagiri in 639 CE, mentioning it as Puphagiri Mahavihara, along with Nalanda, Vikramshila and Tkshila. Puphagiri also was recorded in medieval Tibetan texts. However, unlike Takshila and Nalanda, the ruins of Puphagiri were not discovered until 1995, when a lecturer from a local college first stumbled upon the site. The task of excavating Puphagiri's ruins, stretching over 143 acres (0.58 km2) of land, was undertaken by the Odisha Institute of Maritime and South East Asian Studies between 1996 and 2006. It is now being carried out by the Archaeological Survey of India (ASI). The Nagarjunakonda inscriptions also describe this learning center. 
ASI has launched a major conservation effort, and as of 2007, is acquiring more land in the vicinity of the ruins. Once fully unearthed, the site is expected to become a significant international tourist destination in India. The state government has initiated an annual Buddha Mahotsava at the site.
There are other Buddhist attractions around Langudi hills, the site of Puphagiri. Kaima hill, in its immediate vicinity, contains a unique rock-cut elephant surrounded by four monolithic khondalite pillars; this dates from the Mauryan period in the 3rd century, B.C. Deuli, a hill situated in the confluence of the Brahmani and Kimiria rivers, has preserved five rock-cut Buddhist chambers inside caves. Additional Buddhist sites have been discovered at Bajragiri, Sarapur and Paikrapur. The Langudi sites are perhaps the largest historic Buddhist complex in India.
Langudi can be approached from Jaraka and Chandikhol on the National Highway 5, and is easily accessible from the urban centres of Cuttack and Bhubaneswar. The best months to visit the place are during October and February.
As of 2007, the ruins of this Mahavihara have not been fully excavated. Consequently, much of the Mahavihara's history remains unknown. Of the three Mahavihara campuses, Lalitgiri, in the district of Cuttack, is the oldest. Iconographic analysis indicates that Lalitgiri had already been established during the Sunga period of the 2nd century BC, making it one of the oldest Buddhist establishments in the world.
The recent discovery of a few images of the emperor Ashoka are a major find. Based on this find, it has been suggested that the Puphagiri Mahavihara may have been commissioned originally by Ashoka himself.
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