Fortress Kostajnica

Fortress Kostajnica is a medieval fortified structure in Hrvatska Kostajnica positioned at the border with Bosnia and Herzegovina. It rises from the Una River bank with three towers and thick stone walls that form the core of this regional defensive construction.

The fortress was initially controlled by Croatian noble families before falling under Ottoman rule in 1556. It remained occupied for over a century until its recapture in 1688, when it returned to Croatian hands.

The fortress passed through the hands of several Croatian noble families over time, each leaving their mark on the stronghold as a symbol of local power and authority. This connection to past families shapes how visitors today perceive the site as part of the region's identity.

The site sits along the Una River bank and is best explored on foot, offering views of the river landscape from different vantage points on the grounds. Wear sturdy shoes as the terrain can be uneven and the setting requires careful footing.

The stronghold served as a critical point in a larger defense network of the kingdom, blocking one of the main invasion routes from the south. This strategic location meant its military importance endured across centuries of conflict in the region.