Menacingly towering over the twenty-meter-high hill in the age-old town of Ostroh not far from Rivne, the Ostroh Castle is seen as a token sample of the Ukrainian fortification architecture and is recognized as one of the Volyn’s most interesting historical and architectural monuments.
In the 14th century, the castle complex was raised on the place of the Old Russian town, which was destroyed by Mongolian Tatars in 1241. It remained Ostroh princes’ residence for more than three centuries. They were the richest and the most powerful magnates, who owned a lot of lands on the territory of the modern Ukraine.
Consisting of stone and wooden buildings, the castle was well fortified: it was protected by the steep from two sides and by the deep ditch, dug in place of the former ravine, from the other two. The Ostroh Castle was repeatedly rebuilt and modernized during its centuries-long existence. Two towers – Stone and Round – Epiphany Cathedral with gate belfry, and fragments of defensive walls survived until now. - in: https://discover-ukraine.info/places/western-ukraine/rivne/2328