The Sacellum of San Michele, situated near Saints Nazaro and Celso church in Verona, Italy, is excavated on the slopes of Monte Castiglione, the soft limestone hill that delineates the city. Its origins date back to the 6th-7th centuries, with certain attestations reaching the 8th and 10th centuries. Initially, it served as a rock complex arranged on two levels. However, as the Benedictine monastery nearby flourished, the rock shrine gradually fell into neglect and was eventually abandoned. Presently, mosaics dating back to the 10th century adorn the chapel, along with two overlapping cycles of frescoes. The first cycle dates back to the 10th century, while the second spans from the 12th century. These frescoes have been removed and are housed in the local museum. Originally, the chapel was situated within a cave and consisted of three rooms: one vaulted, one flat, and one open at the top. Over time, the chapel underwent a transformation, halving its size and replacing the rocky walls with masonry elements. This transformation is believed to have occurred during the 15th century. Given the nature of sacellum, a multidisciplinary approach is essential for its preservation. The project was conceived through collaborative efforts among various specialized figures, each contributing their unique expertise to the definition of the project’s objectives. The primary focus is on enhancing the seismic behavior of the entire complex. To address the seismic and static safety, both the geotechnical engineer and the structural engineer have been engaged. Geotechnical engineers assessed the rock component, while structural engineers evaluated the manufactured structural elements. Conservation architect, coordinating the team, formulated conservation project to safeguard the historical and artistic material from potential loss induced by structural interventions. The paper presents a comprehensive analysis of the project, encompassing field and documentary studies, analyses, project planning, and construction site observations.