Rumelihisarı stands as a grand medieval fortress along the European shore of Istanbul, positioned beneath the Second Bosphorus Bridge. Constructed in the first half of the 15th century, the castle features tall stone towers and massive walls that are visible from far across the water.
The castle was originally named Boğazkesen in Turkish and Laimokopia in Greek. Both names mean "strait-blocker" or "throat-cutter," highlighting the fortress’s key purpose. Built by the Ottomans, Rumelihisarı was designed to control the Bosphorus Strait and cut off vital supply routes from the Black Sea to the crumbling Byzantine Empire. This strategic move played a crucial role in the conquest of Constantinople.
The name "Rumeli" translates to "the Roman land," referring to the European side of the Ottoman Empire. To distinguish it from other places, the prefix "Rumeli" was added, setting it apart from the smaller Anadolu Hisarı, which stands just across the Bosphorus on the Asian side. Today, both fortresses remain as reminders of the region’s layered history and the significance of this waterway through the centuries.
Source - https://en.wikipedia.org/wiki/Rumelihisar%C4%B1