Consisting of three huge towers joined by crenellated defensive walls, the fortress was raised in a hurry as part of Mehmet II's master plan to capture Constantinople. Facing the 14th-century castle of Anadolu Hisarı (already in Ottoman hands) across the Bosphorus' narrowest stretch, Rumeli Hisarı was designed to cut maritime supply lines and isolate Constantinople from its allies.
For this, it earned itself the evocative nickname Boĸazkesen, the 'Throat-Cutter'. Designed by the sultan himself, work was completed in August 1452, just four months after it commenced. Garrisoned by Janissaries and bristling with cannon, Rumeli Hisarı proved its effectiveness immediately: a Venetian merchant vessel that attempted to run the blockade was promptly sunk.
Having helped secure the Ottoman conquest of Constantinople, the castle lost its military importance and was downgraded to a prison. The castle was restored by the government in 1953. Today, visitors are free to clamber around the walls, enacting childhood fantasies.
An open-air theatre in the courtyard hosts popular musical events throughout the summer.