Dome structures stand as timeless icons of historical architecture, reflecting the cultural and engineering ingenuity of civilizations across history. A monumental dome structure is currently under construction in Vaishali, Bihar, as a part of a project to enshrine the Lord Buddha’s original holy relics. This structure has an internal diameter of 37.80 m, an outer diameter 49.80 m and an internal height of 33.10 m above plinth level, to provide ample space for a large gathering as it upholds the region's vernacular heritage. Sustainability and durability of the structure have been prioritized and achieved through the dry-joint stone masonry construction. The dome features approximately forty thousand stone units forming a unique semi-spherical hollow shell. The design of the structure carries significant challenges due to its location in a high-seismic region (zone V). To address this, a novel three-dimensional (3D) interlocking arrangement is proposed to enhance its seismic performance. This study also demonstrates compatibility tests between historic and new bricks and mortar, recreated in the laboratory using modern materials, with the aim of identifying suitable substitutes for conservation and restoration of historic masonry, through an analysis of their pore structure and other material characteristics. Subsequently, finite element analysis of the dome has been performed incorporating realistic interaction between masonry units. This pioneering construction is a major contribution towards the built heritage structure with innovative engineering solutions.