The subterranean secrets hidden beneath Istanbul's modern streets

Countries & Cities · Published 23 October 2026 Swipe more like this →

In short: Modern Istanbul sits atop a literal labyrinth of history. While the city above hums with life, a hidden world of Byzantine substructures and ancient debris lies just feet below the pavement, waiting for archaeologists to peel back the layers of time.

Istanbul serves as a profound palimpsest where layers of history are physically stacked on top of one another. Because it served as the seat of the Eastern Roman Empire and a strategic point on the Bosporus Strait, the city contains a dense concentration of overlapping civilizations. Today, this history is often invisible to the casual observer, tucked away in the basements of ordinary buildings or buried under the weight of modern infrastructure.

Archaeologist Ferudun Ozgumus has spent over 20 years identifying these hidden spaces, uncovering more than 300 sites to date. His work reveals that these underground areas are not just ruins but complex structures, such as Byzantine-era substructures featuring arches that can reach at least 20 feet in height.

By analyzing the specific thickness of bricks, the color of the mortar, and the type of masonry—such as hewn stone versus thinner, rust-colored bricks—researchers can pinpoint the era in which a structure was built. The preservation of these spaces is often accidental. Some have been kept intact beneath modern businesses, like a carpet shop, while others are unearthed by large-scale engineering. For instance, the Marmara Project—a massive initiative to build a 76-kilometer immersed tunnel under the Bosphorus—has frequently interrupted construction to recover artifacts from the city's buried past. These discoveries remind us that the city's expansion is a constant negotiation with the ghosts of its previous empires.

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