Heritage sites and monuments embody history, value, and the region’s identity, symbolizing its past and uniqueness. The Bamuni Hills ruins in Sonitpur, Assam, India represent the memories of the ancient panchayatana group of temples dating back to the ninth–tenth century CE, housing a significant collection of temple remnants such as stone figurines and rock sculptures. Unfortunately, the remains have undergone substantial deterioration due to various natural factors in recent decades. To address the study questions, extensive background studies and literature reviews were utilized as secondary data to understand digital preservation and heritage sustainability. Additionally, primary data were collected through site assessments and personal interviews with various professionals. A questionnaire survey was also conducted to gather user perspectives and expand the research understanding. Based on the collected data, the research gaps and study needs were identified. The study presents the meticulous implementation of design methods aimed at preserving the exquisite artifacts of the heritage monument at Bamuni Hills. The proposed methodology includes utilizing photogrammetric documentation, combining terrestrial and aerial photogrammetric data with close-range photography to create a unified dataset. This dataset is subsequently utilized to produce 3D point clouds data to create accurate 3D reconstructions while ensuring alignment and synchronization of data for a seamless workflow. Finally, a proposed model is designed to preserve the substantial ruins within an immersive virtual archive, allowing users to experience historical ruins in ways that transcend the limitations of physical reality.