Located at the narrowest point of the Bosphorus in Istanbul, where the Göksu River meets the strait, Anadolu Hisarı is one of the city’s most impressive structures, both in terms of its location and its history. Rising on a strategic triangular piece of land, the fortress has been known throughout history by names such as Akça Hisar, Gözlüce Hisar, Güzelce Hisar, Yenice Hisar, and Nova Castrum. The builder of the structure is the Ottoman sultan Yıldırım Bayezid.

After defeating the Crusader army at the Battle of Nicopolis in 1396, Yıldırım Bayezid turned his attention to Byzantium and began preparations for the siege of Istanbul. As part of these preparations, he had a defensive fortress built on the Anatolian side of the Bosphorus to prevent aid from reaching Byzantium via the Black Sea. This fortress not only served as a military base but also became the nucleus of the first settlement in the area. Over time, with the settlement of commanders (dizdars), guards, and their families, a neighborhood formed around the fortress.

In 1452, as part of his preparations for the conquest of Istanbul, Sultan Mehmed II (Mehmed the Conqueror) strengthened Anadolu Hisarı and had a large outer wall with three towers (hisarpeçe) constructed around the castle. Thus, the structure evolved from a medieval defensive design into a more aggressive architecture suitable for the siege tactics of the early modern era.

After the conquest of Istanbul, Anadolu Hisarı largely lost its military importance but continued to be used for Bosphorus security for some time. From the 16th century onwards, it also became a place where certain statesmen were imprisoned. In the 17th and 18th centuries, it served as an important defense point against Cossack raids from the Black Sea, but with the construction of new fortifications further up the Bosphorus, this role diminished.

Today, Anadolu Hisarı continues to exist not only as a military structure but also as a historical heritage that has left a deep mark on Istanbul's memory. Along with Rumeli Hisarı on the opposite shore, Anadolu Hisarı was one of the most important elements of the Ottomans’ strategy for besieging Istanbul, and it is now maintained with a museum concept.

Enriched with exhibition and cultural event areas, Anadolu Hisarı continues to bring the traces of the past together with today’s visitors.