English: Udayagiri (Odia: ଉଦୟଗିରି) is the largest Buddhist complex in the Indian state of Odisha. It is composed of major stupas and monasteries (viharas). Together with the nearby complexes of Lalitgiri and Ratnagiri, it is part of the "Diamond Triangle" of the "Ratnagiri-Udayagiri-Lalitgiri" complex. It used to be thought that one or all of these were the Pushpagiri Vihara known from ancient records, but this has now convincingly located at a different site. Per epigraphical artifacts found at the site, Udayagiri's historical name was "Madhavapura Mahavihara." This Buddhist complex, preceded by the Ratnagiri and Lalitgiri sites, with their monasteries, is believed to have been active between the 7th and the 12th centuries.