Photo: Izabela Miszczak · CC BY-SA 4.0 · via Wikimedia Commons
Catacombs & Underground · Turkey
Theodosius Cistern
The open question
Built, used, sealed and forgotten. Why does that keep happening with what's under our cities?
On the record
The Theodosius Cistern is one of many ancient cisterns of Constantinople that lie beneath the city of Istanbul, Turkey.
- Year
- 1912
- Kind
- tunnels

