Architectural conservators in Spain have announced the successful completion of a pilot project using bio-mineralizing bacteria to reinforce the 3rd-century Roman Walls of Lugo. The UNESCO-listed site had been suffering from internal structural decay caused by centuries of moisture infiltration. By injecting a specialized bacterial solution into the mortar, the team triggered a natural process where the microbes secrete calcium carbonate, effectively 'growing' a new mineral bond within the cracks of the stone without changing the wall's outward appearance.
This self-healing heritage technology is being hailed as a major breakthrough for the preservation of stone monuments worldwide. Unlike synthetic resins, the bio-mineralization process is breathable and chemically identical to the original limestone, preventing the long-term stress issues caused by traditional cement-based repairs. The project, funded by the European Heritage Innovation Fund, will now be scaled to other vulnerable Roman fortifications across the Mediterranean.