The Hagia Sophia, a historic landmark in Istanbul, has revealed a hidden network of seven underground tunnel lines, estimated to be around 1,600 years old. This discovery, made during a restoration campaign, adds a new layer of intrigue to the long-standing stories about what lies beneath the iconic monument. The tunnels were found alongside a hypogeum, an underground burial complex, during cleaning and survey work in the garden areas surrounding the structure. The restoration program, led by Turkey's Culture and Tourism Minister Mehmet Nuri Ersoy, is being conducted under scientific oversight, with a focus on the building's long-term safety. The underground work is part of a larger, multi-stage restoration process that includes scanning, modeling, and material analysis across the site. During the cleaning operations, 1,068 tons of soil fill were removed, along with 102 tons from a separate underground burial area, revealing multiple underground 'spaces' and linked tunnels in the western and northern garden areas.
This isn't the first time the subterranean story of Hagia Sophia has come to light, but the latest documentation is unusually detailed. Professor Hasan Fırat Diker, an expert in mapping and understanding the monument's underground infrastructure, emphasizes the practical functions of the tunnel and culvert systems, which are crucial for ventilation and water management. These systems are not romantic 'escape routes' but essential for the building's functionality. The timing of the restoration also reflects a broader concern: Istanbul's earthquake risk and the need to understand the monument's foundation and structural integrity. Modern engineers are focusing on vulnerable points while avoiding heavy-handed interventions that could 'alienate' the building.
The discovery of these ancient tunnels adds to the rich history of Hagia Sophia, a city built with water below its feet. The present Hagia Sophia was built in 532-537 AD under Emperor Justinian I, after earlier churches on the site were damaged or destroyed. It has been repaired repeatedly following earthquakes, making hidden infrastructure just as vital for its survival as the dome above. The Basilica Cistern, a short walk away, is a public example of how Byzantine Istanbul managed water on a vast scale, and the newly documented tunnel lines may help researchers understand drainage, humidity, and maintenance practices in different phases of the city's history without relying solely on myths and legends.
The restoration work, which includes scaffolding, façade cleaning, and structural checks, aims to preserve the building for centuries. The process is as important as the progress, as Ersoy emphasizes, ensuring that scientific assessments and contemporary restoration requirements are met. This approach is crucial in a city like Istanbul, where the underground infrastructure, such as cisterns and conduits, has shaped the historic city and continues to play a vital role in its survival.
