Abstract. The three-dimensional (3D) preservation and repair of historic sites are increasingly in practice using modelling and digital documentation. This study focuses on replacing conventional techniques of historical documentation by creating a digital documentation procedure employing laser scanning for 3D mapping of a monument located in Prayagraj, India. To quickly record the entire monument structure, four scanning stations were planned, where three for the facades and one for the interior. A 3D structure of the monument and its elements dimension that included structural, architectural, historical, and non-engineering information was the end product. Researchers, architects, and conservationists can use this laser scanning-based technique to analyze data in great detail to identify weaknesses and conservation requirements. In order to preserve the monument's cultural relevance, it can also be used for virtual tours. Digital documentation can also provide an accurate monument record for restoration needs, protecting the monument from human- or natural-caused damage. Overall, 3D Modelling and digital documentation are valuable tools in heritage conservation, providing comprehensive records of heritage sites and aiding in practical conservation and restoration plans while making cultural heritage accessible to a broader societies.