**1. Introduction**

Seven century's *Somapura Mahavihara* was listed as world heritage under the title of "ruins of the Buddhist Vihara at Paharpur, Bangladesh" by UNESCO in 1985 AD. The ruin of Paharpur Vihara is located at Naogan District, Rajshahi Division in Bangladesh. This vihara was known to the heritage residents as a hill in Bangla as *Pahar*. Because it was totally buried before archaeological exploration (1807–1812: Buchanon Hamilton, under the survey in Eastern India between [1]) and excavation in the last half of the 18th century to the first half of the 19th century. It was unfolded step by step through the excavations (1879 to 1932) [2] and visible as a vihara with a central shrine. It comes out with series of terracotta

plaques. Based on the ground plan, it has been characterised as a Mahavihara. However, a debate has been raised among the excavators and later researchers about the predictive stylistic pattern of the central shrine. The dominating ideas are cruciform style, *chaumukha* Jain temple, *Sarvatobhadra* style, and *Vajrayana* Style [3]. Nevertheless, these stylistic forms failed to predict the perspective of this shrine.

These days, there are number of software have been developed to generate 3D predictive modelling (e.g., [4]), visualisation, and digital conservation through virtual reality (VR) (e.g. [5]). It can be considered as a known to unknown journey of cultural heritage. Following the London Charter of 2006 and Seville Principles of 2011 are followed to generate the 3D predictive modelling and VR for visualisation and digitally preserve the world's cultural heritage of the Buddhist Vihara of Paharpur. The norms of digitalisation of cultural heritage have not been officially initiated by UNESCO, and ICOMOS did not ratified it by the general assembly [5]. Therefore, the London Charter of 2006 and the Seville Principle of 2011 are widely accepted to digitalise the cultural heritage, which also been followed to systematise this research.

The essence of this initiative, particularly for generating predictive 3D modelling of Paharpur Vihara or *Somapura Mahavihara* is: First, philosophising the vihara architecture of the Bangla region by following the *Vajrayana* Buddhism. Second, information technology and archaeological data enable the 3D model generation of a known structure, producing high-quality outputs of the historic site for digital conservation. And third, predictive 3D modelling can be achieved with the support of the integrated and interactive consideration of data and the guidance of an established methodology for the regeneration of cultural heritage.
