Protecting World Heritage: Paths for UNESCO Recourse and the Case of the Hagia Sophia

In July 2020, Turkish President Erdoğan made international headlines by announcing that the Hagia Sophia would be converted from a museum to a mosque.[1] Hagia Sophia has famously transitioned in religious use throughout its centuries-long existence, originally established as a Byzantine Christian cathedral, later transformed into a mosque in 1453, and penultimately designated as a museum upon the establishment of the Turkish Republic.[2] In its role as a location of religious significance to two Abrahamic faiths, it is widely regarded as an international symbol of religious tolerance and unification.[3]

The Hagia Sophia’s significance as a site of immense religious and cultural value also makes it a flashpoint of political tensions. The property’s status is representative of longstanding Greek-Turkish tensions due to the site’s central importance to the Eastern Orthodox church.[4] Turkey’s ratification of the 1983 World Heritage Convention (“WHC”) dedicated the country to certain international legal commitments for its preservation, and Hagia Sophia’s inscription (as a part of “Historic Areas of Istanbul”) on the list of the United Nations Educational, Scientific, and Cultural Organization (“UNESCO”) World Heritage Sites in 1985 further reinforced international expectations that the complex would remain a museum. Given its global recognition as a site of significance to humanity, it is unsurprising that its 2020 conversion was met with widespread concern.[5]

While it appears its status as a mosque is settled as a matter of Turkish law, questions remain about UNESCO’s potential mechanisms for recourse regarding the site’s preservation.[6] The historic site has incurred increased levels of damage and vandalism since its transformation into a mosque, and archaeologists have raised alarm regarding its continued protection.[7] However, UNESCO’s possible courses of action to attempt to preserve Hagia Sophia’s historic integrity are limited.[8] This blog will examine the feasibility of UNESCO delisting, one of the agency’s only options in addressing disputes over site integrity and preservation.

Immediately following the July 2020 decision to re-convert the Hagia Sophia to a mosque, international stakeholders within UNESCO and similar institutions expressed disapproval of the action. UNESCO issued a statement expressing significant concern the day the redesignation was announced.[9] Later that year, the agency initiated a review process and “sent a mission to the property from 5 to 9 October 2020 […] to look in detail at each of the potential implications of [the] change in status, and their impact on the Outstanding Universal Value of the property.”[10]

The mission findings were presented during the 44th Session of the UNESCO World Heritage Committee. The committee expressed “grave concern” for the site and requested that Turkey provide “an updated report on the state of conversation” of Hagia Sophia.[11] Turkey’s Foreign Ministry issued a statement in response, insisting that the status and administrative changes “have no negative impact as per UNESCO standards.”[12] The statement further asserted Turkey’s sovereign ability to control the property as it chooses.[13]

Despite the Foreign Ministry’s insistence that its status change resulted in no negative impact to the property, experts in cultural heritage have expressed concern about worsening conditions at the Hagia Sophia. İlber Ortaylı, a prominent Turkish expert in Ottoman sites, recently warned that the property is unable to accommodate the influx of tourists and worshippers.[14] Footage of crumbling concrete within the main structure circulated in 2022, prompting Şerif Yaşar, Chairman of the Board of the Turkish Art History Association, to express concern that the structure could collapse during the next Istanbul earthquake if sufficient restoration efforts are not undertaken.[15]

Damage and vandalization are not necessarily inherent to Hagia Sophia’s new status as a mosque, however, online documentation indicates that something in the property’s current administration is simply not working.[16] Further, UNESCO’s statements of concern regarding the site’s maintenance have fallen on deaf ears in Turkey. Accepting that the Hagia Sophia’s architectural and structural integrity are at a turning point, it may be time for UNESCO to consider a rarely used approach for recourse.

The main compliance mechanism of the WHC is its Reporting and Monitoring System, which, in theory, could provide UNESCO with adequate information to support possible delisting of a site from World Heritage Site status.[17] If UNESCO has sufficient evidence to support that the state is not complying with conditions under the convention, UNESCO could take action to delist a site or bring the site’s future inclusion on the list into question. States have many reasons to avoid delisting, including reputational damage and interest in preserving the considerable tourist revenue that comes with such sites.[18]

Given the limited penalties UNESCO can exert against a state which fails to preserve a site, delisting is one of the only serious tools the agency can employ to encourage compliance. World Heritage Sites must display “Outstanding Universal Value,” which is harmed if vandalism and damage to the site is rampant. The convention’s revised 1980 operational guidelines provide the basis for the delisting process. Para. 194 of the operational guidelines stipulates how information for delisting can be gathered in the event the state party itself does not inform the World Heritage Committee of the threat to its site.[19]

Delisting a UNESCO World Heritage Site is rare, and thus far has only occurred in three instances where the fundamental integrity of the location was at risk.[20] The case of Bagrati Cathedral and the Gelati Monastery (former joint World Heritage Sites in Georgia) is perhaps the most instructive for the Hagia Sophia case. Due to concerns about reconstruction and restoration of the site, UNESCO permanently delisted the Bagrati Cathedral in 2017.[21] Prior to the delisting, a UNESCO mission expressed concern regarding the government’s repurposing of the site to accommodate original religious functions – to convert it from a museum to an active church.[22]

During its process of review, UNESCO issued multiple statements of concern and called on the Georgian government to devise a management plan for Bagrati Cathedral.[23] The Georgian government moved forward with the construction regardless, and as a result, UNESCO added Bagrati Cathedral and Gelati Monastery to its “List of World Heritage in Danger.”[24] This action prompted increased dialogue and cooperation from the Georgian government, and UNESCO opted to restore Gelati Monastery’s World Heritage status.[25] Unfortunately, UNESCO determined in 2017 that the construction at Bagrati Cathedral irreparably damaged the “Outstanding Universal Value” of the property and removed the cathedral from both the World Heritage List and the List of World Heritage in Danger.

Delisting or removal of a site to the List of World Heritage in Danger are two of UNESCO’s primary tools in motivating state compliance with the WHC. In the case of Bagrati Cathedral, where the government sought to redesignate a site for religious practice, UNESCO’s actions at least elicited renewed action to preserve another site. It is possible that, in certain scenarios, UNESCO delisting may accelerate or reinforce damaging state action at a site. To better understand the efficacy of UNESCO’s options in encouraging state preservation of a site, additional research should be done regarding state response and management of sites after delisting. The Hagia Sophia is a priceless symbol of immense religious and historic value, and UNESCO should explore all the tools at its disposal to preserve the site’s integrity for all of humanity.

  1. Carlotta Gall, Turkey’s Erdogan Signs Decree Allowing Hagia Sophia to be Used as a Mosque Again, N.Y. Times, (July 24, 2020),
  2. Edhem Eldem, The Reconversion of the Hagia Sophia into a Mosque: A Historian’s Perspective, 8 J. Ottoman & Turkish Stud. Ass’n 243, 244 (2021).
  3. ‘Keep Turkey’s Hagia Sophia ‘A Space for Meeting of Cultures,’ UN Rights Experts Urge, U.N. News (July 31, 2020),
  4. Yesim Dikmen, Orthodox Patriarch Says Turning Istanbul’s Hagia Sophia Into Mosque Would Be Divisive, Reuters (June 30, 2020),
  5. Michael Goodyear, Heaven or Earth: The Hagia Sophia Re-Conversion, Turkish and International Law, and the Special Case of Universal Religious Sites, 19 UCLA J. Islamic & New Eastern L. 51, 53 (2021).
  6. See The Hagia Sophia Case: Turkey’s Highest Administrative Court Annuls Ataturk’s 1934 Decision Converting the Hagia Sophia into Museum, 134 Harv. L. Rev. 1278, for an analysis of the legality of the 2020 re-designation under Turkish law.
  7. Archeologists and historians have turned to documenting incidents of vandalism on social media, see Francesca Aton, Hagia Sophia’s Marble Floors Suffer ‘Tremendous Damage’ from Cleaning Mishap, ARTNews (June 30), 2022,; See also @SanatTarihiSTD, X (Apr. 18, 2022, 3:35 AM),
  8. Oliver Wainwright, UNESCO Impotence Takes Shine Off World Heritage Status, The Guardian (July 2, 2015),
  9. “UNESCO deeply regrets the decision of the Turkish authorities, made without prior discussion, and calls for the universal value of World Heritage to be preserved.” UNESCO Statement on Hagia Sophia, Istanbul, UNESCO World Heritage Convention (July 10, 2020),
  10. Statement by the Director of the UNESCO World Heritage Centre, on Hagia Sophia, Istanbul, UNESCO World Heritage Convention (Nov. 14, 2020),
  11. Turkey Hits Back at UNESCO Over Hagia Sophia, Deutsche Welle, (July 24, 2021),
  12. Press Release, Tanju Bilgiç, Spokesperson of the Ministry of Foreign Affairs, Statement of the Spokesperson of the Ministry of Foreign Affairs, Ambassador Tanju Bilgiç, in Response to a Question Regarding the Decision Adopted on “Historic Areas of Istanbul” During the Extended 44th Session of the UNESCO World Heritage Committee (July 21, 2021),
  13. Id., “The functional usage of the Hagia Sophia… [is] solely related to Turkey’s sovereign rights.”
  14. İlber Ortaylı’dan Ayasofya Uyarısı: ‘Taşıyacak Güçte Değil’, Cumhuriyet (Sept. 17, 2023),
  15. İsmail Arı, Camiye Dönüştürülen Ayasofya Dökülüyor: Beton Parçalarının Düştüğü Görüntüler Ortaya Çıktı, Bir Gün (Nov. 28, 2023),
  16. Kate Fitz Gibbon, Turkey – Hagia Sophia Suffers Serious Damage: Walls Peeled and Marble Tiles Shattered, Cultural Property News (July 1, 2022),
  17. UNESCO May Strip Hagia Sophia and Chora of World Heritage Site Status, Bianet English, July 26, 2021),
  18. Monica Pitrelli, Being Named a UNESCO World Heritage Site is a Big Deal – So is Losing It, CNBC (Apr. 27, 2021),
  19. Eike Albrecht & Benedicte Gaillard, Procedure for Delisting a Site From the World Heritage List: Is Delisting With Consent or Against the Wish of a State Party Possible? 3 J. Tourism & Hospitality Mgmt. 15, 16-7 (2015).
  20. UNESCO, The Operational Guidelines for the Implementation of the World Heritage Convention, UNESCO World Heritage Convention (Sept. 24, 2023),
  21. See UNESCO, Historical Monuments of Mtskheta and Bagrati Cathedral and Gelati Monastery 3-39 (2008), “The mission recommended that the authorities immediately start preventive conservation work on the Bagrati Cathedral and Gelati Complex, and develop, in coordination with the World Heritage Centre and Advisory Bodies, a long-term programme for the systematic conservation of the mural paintings and mosaics with the involvement and collaboration of international specialists in this domain.”
  22. Id. at 6 (“The mission was informed of the State Party’s intention to prepare a new reconstruction project for Bagrati Cathedral in order to recreate its initial religious use and functions. Recalling earlier discussions among the Advisory Bodies, international experts and the World Heritage Committee, as well as noting that in accordance with Paragraph 86 of the Operational Guidelines the reconstruction of historic buildings is justifiable only in exceptional circumstances, the mission requested that the authorities provide to the World Heritage Centre and Advisory Bodies complete and detailed documentation concerning this project for review by the World Heritage Committee”).
  23. Id.
  24. Pitrelli, supra note 18.
  25. Nino Gugunishvili, World Cultural Monument Heritage Status Returned to Gelati Monastery, Georgia Today (July 11, 2017),