Ključ Castle

Ključ, Una-Sana Canton, Bosnia and Herzegovina, Bosnia and Herzegovina

---

Ključ Castle is a medieval fortress located above the town of Ključ in the Una-Sana Canton of Bosnia and Herzegovina. It stands on an elongated slope of high rocks, dominating the valley of the Sana River, at an altitude of about 521 meters.

The site originally had ancient fortifications dating back to Roman times, but the current castle was built in the 13th century. It was a strategically important stronghold overseeing a key crossing of the Sana River and controlling traffic through the valley connecting multiple regions. The fortress has a complex structure with defensive walls and towers, including the Lubica tower, and featured a secret passage to the river for water supply.

Ključ Castle played a pivotal role in Bosnian history, most notably as the place where the last Bosnian king, Stjepan Tomašević, surrendered to the Ottomans in 1463, marking the end of Bosnia’s independence and the start of Ottoman rule. Today, it is a preserved ruin recognized as a national monument of Bosnia and Herzegovina and offers scenic views over the surrounding landscape and the Sana valley.

The site is surrounded by a pine forest, contributing to a peaceful natural environment for visitors to explore and enjoy.