Since the beginning of the 16lh century and until 1939 the village of Olyka in Volyn was one of the family estates of the Radzyvils, who were the oldest princely family in Europe. The prince’s palace and a grand collegiate church, which is an architectural gem of Volyn, have preserved up to nowadays.

Olyka became a possession of the Radzyvils at the beginning of the 16th century. In 1586, it became an entailed estate, i.e. it was impossible to sell or split it, and it was always inherited by eldest sons. Since 1547 the Radzyvils had a title of Prince of Olyka and Nesvizh. In 1558 – 1564, Mykola Radzyvil Chorniy constructed Olyka Castle, the first castle of bastion type in Ukraine. In 1640, Albrecht Stanislaw Radzyvil turned the castle into a palace complex. Instead of fortress walls there appeared palace buildings, which formed a sguare yard. The entrance into the courtyard was crowned by a tall tower in the Barogue style. As before, the castle was still defended by bastions that were armed with 202 cannons and a large garrison.

Nowadays, buildings of the former castle house a sanatorium, but the territory is open for tourists.