<p>Lime, a fundamental construction material used worldwide, is valued for its durability and adaptability across a range of architectural forms. It stands out for its low carbon footprint during production and its ability to sequester carbon throughout its lifespan, making it a key asset in sustainable construction. Commonly applied in mortars, renders, and plasters, lime remains indispensable. However, ancient lime-based structures require specific maintenance techniques to preserve both their aesthetic appeal and structural integrity, thus ensuring the longevity of these culturally significant sites. Yet, shortages of high-quality limestone raw materials, coupled with the commercial addition of finely ground limestone powder in hydrated lime, now present considerable challenges. This study investigates the production of natural hydraulic lime (HL), focusing on how the chemical and mineralogical composition of raw materials, particularly limestone, affects its properties. Various limestone samples underwent mineralogical analysis through techniques such as Scanning Electron Microscopy (SEM), X-Ray Fluorescence (XRF), Fourier Transform Infrared Spectroscopy (FTIR), and X-Ray Diffraction (XRD). These analyses provided valuable insights into the optimal material composition for NHL production, highlighting which types of lime are best suited for maintaining historic structures. Furthermore, a comparative analysis was conducted to evaluate performance differences between these hydraulic limes and industrial hydraulic lime. The findings confirm the compatibility of these hydraulic limes with traditional Moroccan construction requirements, underscoring the importance of selecting appropriate materials to preserve the architectural integrity of cultural monuments, which can also lead to significant reductions in labor and material costs. Notably, L5 and L6 were successfully applied in the restoration of Marrakech’s ancient medina, demonstrating their effectiveness in conserving historic structures. Overall, this research enhances knowledge on the use of compatible repair materials that honor cultural heritage while addressing contemporary environmental challenges. This research proposes a sustainable model for heritage conservation that addresses local needs by balancing preservation, environmental sustainability, and community benefits within the framework of the United Nations Sustainable Development Goals (SDGs).</p>