Otocac was until the 18th century, was situated on a natural island in the river. The island was fortified by walls and towers for defense. She tells him it could only by boat across the water. It made ​​him impregnable in its long history Otočac was never conquered. In the city there are traces of life in older times. Japodi lived in the forts and Umac Vinici, while no fort Zorišnjak the Old Village was not far away. These archeological ruins are not further explored.