Istanbul's Heritage Archives Race to Replace Thousands of Duplicate Digital Images This Week

Istanbul's leading cultural preservation bodies moved this week to tackle a problem that has quietly undermined digital archiving efforts across the city: tens of thousands of duplicate image files cluttering the databases used to document historic neighbourhoods, archaeological sites, and Ottoman-era structures. The Istanbul Metropolitan Municipality's Directorate of Cultural Heritage confirmed on Thursday that a system-wide deduplication project entered its operational phase on July 1, targeting archives spread across at least six municipal departments.

The timing matters. Turkey's broader push to digitise heritage records accelerated sharply after the February 2023 Kahramanmaraş earthquakes exposed how fragile analog and poorly managed digital archives can be when disaster strikes. Istanbul, sitting atop the North Anatolian Fault, has its own seismic clock ticking — and officials have repeatedly acknowledged that losing photographic documentation of the city's built fabric would compound any structural losses. A duplicate-heavy database is not just a storage nuisance; it slows retrieval, inflates costs, and creates version-control chaos when emergency teams need accurate records fast.

What the Deduplication Drive Covers

The project is running across three primary institutions this week. The Istanbul Archaeological Museums complex in Sultanahmet — which holds records tied to Byzantine, Roman, and Ottoman material culture — is processing an estimated archive of several hundred thousand image entries, many accumulated during rapid digitisation drives between 2018 and 2022. The Atatürk Library in Taksim, which houses the city's primary municipal photographic collection, began its own parallel audit on Monday. A third workstream is running inside the KUDEB units — the municipal offices responsible for authorising restoration work on registered historic buildings — where duplicate site-survey photographs have reportedly created version conflicts during permit reviews.

The deduplication software being deployed uses hash-based matching, a standard approach that flags files with identical pixel-level content regardless of filename or folder location. Project coordinators are reportedly conducting manual review of flagged pairs where metadata differs, to avoid deleting images that may look identical but carry different provenance or dating information — a real risk when dealing with archive photographs of façades in neighbourhoods like Balat, Fener, and Kuzguncuk, where streetscapes changed incrementally over decades.

Staff from the Greater Istanbul Municipality's information technology division are embedded with archivists through at least July 18, the stated end date for the first review phase. A second phase, covering satellite municipality archives in districts including Fatih and Beyoğlu, is scheduled to follow.

Scale of the Problem and What Comes Next

Digital redundancy in municipal heritage archives is not unique to Istanbul, but the scale here reflects the speed of digitisation without corresponding quality control. According to documentation published by the Turkish Ministry of Culture and Tourism in its 2024 digital transformation report, institutional image repositories across Turkey's major cities contained duplication rates ranging between 18 and 34 percent — figures that translate directly into inflated storage costs and degraded search functionality.

For conservationists working on active restoration projects along İstiklal Caddesi or in the Süleymaniye district, the practical effect of a cleaner archive is faster access to baseline imagery when assessing change over time. KUDEB inspectors comparing pre- and post-restoration façades depend on accurate dating metadata; a database cluttered with duplicates forces manual cross-checking that adds days to permit workflows.

Residents and researchers who use the Atatürk Library's public reading room in Taksim should expect some digital catalogue disruption through mid-July as records are reindexed. Library staff have advised that physical access to original photograph collections remains unaffected. The Municipal Directorate of Cultural Heritage has indicated it will publish a summary report on the project's outcomes — including the volume of files removed and storage recovered — once the first phase concludes on July 18. That report is expected to inform a longer-term policy on image acquisition standards for all heritage-related municipal departments going forward.