This paper analyzes the impact of the 2020 Beirut blast and the 2023 Syria earthquake on the built heritage of Beirut and Aleppo, focusing on unreinforced masonry (URM) structures. It outlines the architectural typologies of historic buildings in both cities and provides an overview of significant structural interventions implemented after their construction phase. The study classifies the primary types of damage observed in each city, highlighting similarities in damage patterns resulting from both disasters. These include in-plane cracking, out-of-plane deformation, localized failure mechanisms, and failures in the connections between structural elements. An analysis of the underlying causes of these damages, as well as the lessons learned from each disaster regarding original structural design and subsequent interventions, is presented. Additionally, the paper discusses the seismic upgrades applied to the structural restoration of a historical building with slender URM walls and flexible timber floors in Beirut. A nondestructive testing campaign, which included operational modal analysis, was carried out, supplemented by a multidirectional finite element mass pushover analysis conducted before and after the consolidation process. Applying these structural interventions resulted in a significant increase in the lateral performance of the considered historical building, demonstrating improvements in lateral capacity, clearer global mode shapes, and overall box-like behavior.