Byblos Heritage and Conservation of Saint John-Mark’s Crusader Church, Located in Jbeil

The most ancient, constantly populated cities in the whole world, Byblos (Jbeil), has the Saint John-Mark Crusader Church, a remarkable representative of Romanesque ecclesiastic buildings constructed in 1115 CE. The study aimed to focus on the architectural and historical value of the church, the analysis of its condition regarding the modern structure, and the suggestion of a proper conservation plan. This study indicated the significant problems of deterioration related to moisture penetration, vermin growth, the inappropriateness of modern materials, and perceptual intrusions into the church’s authenticity. Despite these problems, the church still has its original space plan, such as a basilica construction, a vaulted heaven, and a separate dome of the baptistery. The conservation plan suggested the architectural restoration approach, which implies applying lime mortars, eliminating intrusive components, and filling the cracks. Also, a green environmental plan is included to improve the site’s ecological sustainability and aesthetics. The church’s cultural, religious, and touristic value could be retained in the urban context of Byblos through careful restoration of the interventions.