Turkey has embarked on a restoration project aimed at preserving the Hagia Sophia, one of Istanbul's landmarks. The Turkish Culture and Tourism Ministry has initiated a 50-year plan to reinforce the structure, focusing primarily on making its dome more resistant to earthquakes, according to Greek Reporter.
The restoration, which began approximately three years ago, is set to be the largest in the Hagia Sophia's history. The work will concentrate on the dome, walls, and minarets, with dome restoration scheduled to commence on April 14, 2025. The objective is to "eliminate the centuries-old fatigue" of the structure and ensure its longevity for future generations.
To preserve the architectural integrity and historical authenticity of the Hagia Sophia, all interventions will be conducted from the exterior. This approach is intended to prevent any damage to the mosaics that adorn the interior surface of the dome. The existing lead covering on the dome will be carefully removed to reveal the underlying structural condition. Any damaged lead coverings will either be repaired or replaced with new ones.
Ahmet Gulec, a member of the scientific board supervising the restoration, explained the challenges involved in the process. "The underside of the dome is covered in mosaics, making structural intervention from below nearly impossible," he said, as reported by Tempo. "We will use materials and techniques consistent with Ottoman-era construction to ensure the dome is stable and in accordance with its original character."
To facilitate the restoration while allowing the Hagia Sophia to remain open to worshippers and visitors, a steel platform system supported by four columns and standing 43.5 meters tall will be installed inside the mosque. This setup will enable uninterrupted worship and tourist access while work on the inner and outer surfaces of the dome proceeds safely and efficiently.
Mehmet Selim Okten, a construction engineer and lecturer at Mimar Sinan Fine Arts University, is a member of the scientific council overseeing the renovations. "We have been carrying out intensive restoration efforts on Hagia Sophia and its surrounding structures for three years," he said, according to Greek Reporter. "At the end of these three years, we have focused on the seismic safety of Hagia Sophia, the minarets, the main dome, and the main arches, especially due to the expected Istanbul earthquake."
The restoration comes in the wake of a 7.8 magnitude earthquake that struck southern Turkey in 2023, causing widespread destruction and underscoring the vulnerability of historic structures. While Istanbul was not directly impacted, the calamity heightened fears of a similar quake in the city, given its proximity to fault lines.
Hagia Sophia, inscribed on the UNESCO World Heritage List in 1985 under the Historic Areas of Istanbul, has a rich history. Built in 537 CE under Byzantine Emperor Justinian I, it stood for nearly 900 years as a major cathedral of Eastern Orthodox Christianity and a crowning achievement of Byzantine architecture. "Hagia Sophia's grand dome and intricate mosaics symbolized the rich artistic and engineering skills of the Greek-speaking Byzantine world," notes Greek Reporter.
Following the Ottoman conquest of Constantinople in 1453, Sultan Mehmed II transformed Hagia Sophia into a mosque, marking a new chapter in its history. Under Ottoman rule, Christian mosaics were covered, and minarets and Islamic elements were added. Notably, Ottoman architect Mimar Sinan made contributions to the structure, reinforcing it with buttresses and implementing measures that extended its lifespan. His work played a key role in helping Hagia Sophia withstand numerous earthquakes over the centuries.
In 1935, the Turkish Republic converted Hagia Sophia into a museum. However, in July 2020, the Turkish Supreme Administrative Court declared the 1935 decision null and void, leading to its reopening as a mosque after 86 years.
Today, Hagia Sophia remains a functioning mosque and a symbol of Istanbul's enduring heritage. It continues to be one of the city's most prominent tourist attractions, drawing millions of visitors each year. The current restoration aims to preserve the monument in its original form while enhancing its resilience against future earthquakes.
As part of the restoration efforts, a tower crane 41 meters high with a boom length of 60 meters will be installed east of Hagia Sophia. This crane is designed to operate at a safe distance from the building, ensuring that the restoration work can proceed without putting the structure at risk.
The work on the dome will also include the conservation of the mosaics on the interior surface. To prevent damage caused by weather conditions and to safeguard the mosaics, the dome will be temporarily covered with a steel structure and protective tarp during the restoration.
Throughout the process, all structures within the Hagia Sophia complex were documented in three dimensions and transferred to a digital environment, creating a digital twin of the monument. This technological approach allows for precise planning and monitoring of the restoration efforts.
Upon completion of the restoration, the temporary steel covering, platform, and tower crane will be dismantled in the manner they were installed. The Hagia Sophia will thus emerge restored and strengthened, preserving its historical and cultural value for generations to come.
The article was written with the assistance of a news analysis system.